Popular Science Monthly/Volume 10/November 1876/Miscellany

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MISCELLANY.

Supplement to the Glacial Theory.—At the Buffalo meeting of the American Association Prof. W. C. Kerr, State Geologist of North Carolina, read a paper accounting for the presence and characteristics of the drift or unstratified superficial deposits of North Carolina, which cannot be attributed to glacial action or the action of water, and which has hitherto presented a somewhat puzzling problem to geologists. He considers it to be the result of land-slides, or, as he terms them, earth-glaciers, formed from the detritus of the stratified rocks of the foot-hills mixed with water—the mass throughout its whole depth, of from fifteen to thirty feet, being penetrated by the frosts of the glacial epoch, and subject to the same laws of action as real glaciers.

The course of the fragments of different strata, as shales, quartz-veins, etc., can be traced down the slopes, showing unmistakably the mode of action; and the distribution of bowlders and of gold throughout this drift, though otherwise inexplicable, is readily accounted for by this hypothesis.

 

A Note on the Radiometer, by Prof. T. C. Mendenhall, of Columbus, Ohio, explained his method of illuminating this instrument for the purpose of projecting an enlarged image of the arms or fans upon a screen.

The radiometer being suspended vertically, a beam of light is reflected upward through it, and made to fall upon a mirror above, which, with the aid of a projecting lens, produces the image of the movable fans upon the screen. As the beam of light produces no motion when striking these fans edgewise, the most delicate experiments can be made, and their effects seen, without any disturbance caused by the light used in projection.

 

On cooling the Air of Buildings during Hot Weather, by Prof. Simon Newcomb, was a valuable paper, which was practical enough to satisfy those who demand that the value of all scientific labors shall be tried by the test of utility. The failure of the many plans which have been suggested for cooling buildings in summer has arisen from overlooking the fact that the human body is a "wet-bulb thermometer," and that the air needs not alone to be cooled, but to be brought to a condition which will allow speedy evaporation, and that, therefore, contrivances for simply cooling the air have not resulted in a degree of comfort at all commensurate with their trouble and expense. We have but to remember the discomfort of a moist, "muggy" day, even when the mercury marks a moderately low temperature, to see that the air needs not only to be cooled, but to be dried. It will not answer to dry the air by chemical absorption, as by sulphuric acid or lime, on account of the heat of the chemical union.

The only satisfactory way to remove the moisture is by condensation and deposition, and for the purpose of doing this effectually and economically Prof. Newcomb suggests an apparatus. He proposes, by passing the ordinary air of a summer day through an ice-chest, to reduce it to a point far below the dew-point—or, say, 35° Fahr. Thence it should be passed through a very large tin tube on its way to the outside air. Inclosing this cold-air tube, is to be another, still larger, through which warm air from the apartments is to be forced; the two streams passing in opposite directions, the readily conducting substance of the tubes facilitating the vigorous efforts of the hot and cold currents to reach an equilibrium, the moisture being, meantime, rapidly deposited on the large condensing surfaces of the tubes. The outlets of the tubes are to be together, and the resulting mixture would be a volume of dry air at a comparatively low temperature. If, for example, the air in passing through the icebox was reduced to 35°, while the air admitted to the outer tubes was at 95°, the result would be a mixture of dry air at about 70°, which, if mingled in considerable volume with the ordinary air of a room on a hot summer day, would be greatly conducive to comfort. The greatest value of Prof. Newcomb's suggestion is in utilizing the cold air on its passage for the purpose of condensing moisture. As to the quantity of ice needed to cool a given space, Prof. Newcomb was not prepared to give any exact figures., although he had made some estimates. He thought, however, that, at the price of ice in Washington, the cost of cooling the Capitol would be forty or fifty dollars per day.

 

Some New Points regarding the Tongue of the Picus Viridis (green woodpecker) was the title of a brief paper by Dr. Joshua Lindahl, of Sweden, in which he pointed out some errors in the common descriptions of the remarkable extension of the hyoid bones over the skull, which characterizes the woodpecker family. Having occasion to dissect the head of the green woodpecker of Sweden, he observed that the elongations of the posterior cornua of the hyoids, instead of passing symmetrically over the skull and terminating at the posterior end of the bill, as usually depicted in the text-books, were both carried to the right of the median line of the skull, and extended along the right side of the upper mandible, nearly or quite to its tip. Subsequent examination of numerous specimens showed this to be an accidental variation, but characteristic of the genus. A few of the black and pied species were examined, showing the same lack of symmetry, and differing only in the horns or muscles terminating at the base of the bill. Dr. Lindahl offered no explanation of these peculiarities, but called attention to the fact that the food of the green species varied considerably from that of the others, being sought deeper in the trees, and hoped that ornithologists and entomologists would consider the points of sufficient interest to seek their explanation. In the brief discussion which followed, the asymmetry of position and the extension of the muscles to the end of the mandible were spoken of as of interest, and as being new to ornithologists. While it is always important that errors in our text-books should be pointed out and corrected, the assumption that the facts are wholly new would seem to be somewhat hasty.

In this connection it may be sufficient to point out that Huxley ("Anatomy of Vertebrated Animals") says: "The free ends (of the posterior cornua) are inserted between the ascending and maxillary processes of the right pre-maxilla." In the "American Cyclopædia," the point of attachment is stated to be "usually near the opening of the right nostril; "while Wilson, writing early in the century, describes them as follows:" The os hyoides is divided into two branches that pass, one on each side of the neck, to the hind-head, where they unite, and run up along the skull in a groove; descend into the upper mandible by the right side of the right nostril, and reach to within half an inch of the point of the bill, to which they are attached by another extremely elastic membrane. In some species these cartilaginous substances reach only to the top of the cranium; in others they reach to the nostril; and in one species they are wound around the bone of the right eye, which projects considerably more than the left for their accommodation."

 

Bartlett's Ozone-Generator.—An apparatus for the generation of ozone was exhibited to the Association by the inventor, Dr. F. W. Bartlett, of Buffalo.

The machine is divided into three parts, each having a share in the process. The base, or generator, is a glass vessel eight inches high, with a projecting rim at either end; the interior space, four and a half inches in diameter, being divided into eight compartments by projections from the inner wall, extending one and a quarter inch toward the centre. This unoccupied centre has a movable cylinder which, when in position, completes the walls of the separate cavities. In each of these a tablet of phosphorus, one by two inches, and one-eighth of an inch thick, is suspended in water by a fusible wire—the fusible wire being used so that in cases of ignition, which sometimes occurs, the phosphorus may be completely submerged and the flame extinguished. Resting upon the base is a conical cylinder, eight inches high, and with a diameter at the top of five inches, composed of double walls of wire-cloth, between which lies some porous material saturated with a strong alkaline solution. This presents an effectual bar to the passage of phosphoric acids, while it permits the free transit of the ozone. Above this eliminating-chamber is a second glass cylinder about eight inches in height, with an aperture at the top through which passes a glass rod carrying a plunger for displacing the water in the base, and by means of which the tablets of phosphorus may be raised or lowered. The space thus provided above the phosphorus is about eighteen inches, and is considered by the inventor indispensable to the full utilization of the phosphoric vapor in the production of ozone.

In its present form the machine is employed chiefly for disinfecting purposes, and performs such work not only thoroughly but very cheaply. For ozonizing the atmosphere of a house, the slow oxidation of 100 to 150 grains of phosphorus daily will suffice. It is entirely manageable and without any disagreeable odor. Dr. Bartlett claims that ozone possesses very important curative properties, has employed it successfully in numerous cases of asthma, hay-fever, typhoid fever, scarlatina, diphtheria, puerperal fever, erysipelas, etc. He predicts that its introduction will work great changes in the medical treatment of zymotic or malarial diseases. While making due allowance for the enthusiasm of an inventor, it must be admitted that Dr. Bartlett has produced a machine which does well the work for which it was intended.

 

Science in the United States.—Sir William Thomson, in the presidential address to the Physical Section of the British Association, spoke as follows of the work of some of our American scientific men:

"I wish I could speak to you of the veteran Henry, generous rival of Faraday in electromagnetic discovery; of Peirce, the founder of high mathematics in America; of Bach e, and of the splendid heritage he has left to America and to the world in the United States Coast Survey; of the great school of astronomers which followed—Newton, Newcomb, Watson, Young, Alvan Clark, Rutherfurd, Draper, father and son; of Commander Belknap and his great exploration of the Pacific depths by piano-forte wire with imperfect apparatus supplied from Glasgow, out of which he forced a success in his own way; and of Captain Sigsbee, who followed with like fervor and resolution, and made further improvements in the apparatus by which he has done marvels of easy, quick, and sure deep-sea sounding in his little surveying-ship Blake; and of the admirable official spirit which makes such men and such doings possible in the United States naval service. I would like to tell you, too, of my reasons for confidently expecting that American hydrography will soon supply the data from tidal observations, long ago asked of our own Government in vain by a committee of the British Association, by which the amount of the earth's elastic yielding to the distorting influence of sun and moon will be measured; and of my strong hope that the Compass Department of the American Navy will repay the debt to France, England, and Germany, so appreciatively acknowledged in their reprint of the works of Poisson, Airy, Archibald Smith, Evans, and the Liverpool Compass Committee, by giving in return a fresh marine survey of terrestrial magnetism to supply the navigator with data for correcting his compass without sights of sun or stars. I should tell you also of 'Old Prob's' weather-warnings, which cost the nation $250,000 a year, money well spent, say the Western farmers, and not they alone; in this the whole people of the United States are agreed; and though Democrats or Republicans playing the ' economical ticket' may for half a session stop the appropriations for even the United States Coast Survey, no one would for a moment think of starving 'Old Prob;' and now that 80 per cent, of his probabilities have proved true, and General Myer has for a mouth back ceased to call his daily forecasts 'probabilities,' and has begun to call them 'indications,' what will the Western farmers call him this time next year?"
 

The French Association.—The fifth session of the French Association for the Advancement of Science was opened at Clermont-Ferrand, on the 18th of August. In the opening address, the president, M. J. Dumas, sketched the history of the British Association, pointing out the great services rendered by that body in popularizing science. Similar results are to be expected from the French Association. Of the place occupied by science in modern life, he said: "Natural science is no longer content with the contemplative attitude which sufficed for Newton and Laplace. Science is now mixed up with all the personal acts of our existence; she interferes in all measures of public interest; industry owes to her its immense prosperity; agriculture is regenerated under her fostering care; commerce is forced to take her discoveries into account; the art of war has been transformed by her; politics is bound to admit her into its councils for the government of states. How could it be otherwise? Have not mechanics, physics, chemistry, the natural sciences, become intelligent and necessary agents for the creation of wealth by labor? If comfort is more universal, the life of man more prolonged, wealth better distributed, houses more commodious, furniture and clothing cheaper, the soldier better armed, the finances of the state more prosperous, is it not to the sciences that all this progress is due?... Whether we wish it or not, we must needs accept Science as a companion, to possess her or to be possessed by her. If you are ignorant, you are her slave; if you are skilled, she obeys you. The future belongs to science; unhappy are they who shut their eyes to this truth."

 

Japanese Metallurgy.—A writer in the Japan Mail describes as follows the Japanese method of obtaining mercury from its sulphide (cinnabar): The cinnabar is first powdered by means of an iron, boat-shaped mortar, with a circular knife. It is then washed to remove the foreign matter, and to obtain the cinnabar in a finely-powdered state. This is, after being dried, mixed with an equal weight of half-burned charcoal (half coal and half ashes), and the whole is put into an iron pot, which is carefully covered with a round iron cover. This cover has in the middle a round opening, into which a curved tube of iron is fixed and cemented with a mixture of loam, salt, and a little water, the other extremity of the tube ending in a pot filled with cold water. The whole tube is wrapped in some fibrous substance, and kept cool by aid of cold water. The whole is generally heated on a small open charcoal furnace, the quicksilver distilling into the pot of water. This process is founded on the fact that the sulphur of the cinnabar is retained by the ashes, and perhaps, also, by the iron of the inner surface of the pot, the mercury evaporating by the heat. This quicksilver is, however, not pure, but always contains a small quantity of foreign metals (lead, copper, etc.).

 

Action of Light on Selenium.—The action of light in modifying the electrical conducting power of selenium was first observed by May, a telegraph-operator at Valencia, Ireland, who communicated the facts to Willoughby Jones in 1873. The latter having fully confirmed the observations of May, the attention of physicists, both in England and Germany, was drawn to the subject. Within the last twelve months it has been made matter of special inquiry by Prof. Adams and by Dr. Werner Siemens, each carrying on his investigations independently of the other. The results obtained by Siemens are set forth in a lecture delivered at the London Royal Institution by his kinsman, C. W. Siemens. He exhibited the action of light by a contrivance of Dr. Werner Siemens, in which the selenium was in a form in which the surface-action of light can produce its maximum effect. Two spirals of thin wire (iron or platinum) are laid on a plate of mica in such a way that the wires lie parallel without touching. While in this position a drop of fluid selenium is made to fall upon the plate, filling the interstices between the wires; and, before the selenium has bad time to harden, another thin plate of mica is pressed down upon it so as to give firmness to the whole. The two protruding ends of the spirals serve to insert this selenium element in a galvanic circuit. Mr. Siemens calls this disk his "sensitive element." The whole arrangement is no larger than a sixpence. Its action was shown in this way: It was placed in a galvanic circuit, at one end being a Daniell cell, and at the other a delicate index galvanometer. The "disk" was first inclosed in a dark box; the circuit was "made," but no electricity passed through—no movement of the index was seen. The "disk" was then exposed to light; still no action was apparent. Another disk was taken that had been kept in boiling water for an hour, and gradually cooled. In the dark box it gave a slight passage to electricity as indicated by the index, but as soon as the light was admitted the index registered a great passage of electricity. Another disk heated to 210° C, and allowed to cool, was then used, and a greater action still was apparent with this. Dr. Werner Siemens has worked at the meaning of this, but without tables and diagrams it is not possible to convey an adequate idea of his results. The basis of the change in condition seems to lie in the fact of the extent to which the selenium is heated, for, when again allowed to cool, its behavior depends on the extent to which it has been heated. The experiment was shown of the effect of different parts of the spectrum on a disk. The actinic ray produces no effect, but the influence increases as we approach the red end. A selenium photometer was also shown in action, the principle of which is to compare the relative effects of two lights in affecting the conditions for the passage of electricity. At the end of the lecture a most interesting little apparatus was put at work, which Mr. Siemens calls a selenium "eye." There is a small hollow ball, with two apertures opposite to each other. In one is placed a small lens, one and a half inch diameter, and at the other a "disk." The disk is connected with a Daniell cell and a galvanometer, and this represents the retina. There are two slides which represent the eyelids. The action of light on the disk is indicated on the galvanometer. Not only was this shown to be sensitive to white light, but sensitive in different degrees to different colors. Mr. Siemens suggested it would not be difficult to arrange a contact and electro-magnet in connection with the galvanometer in such a manner that a powerful action of light would cause the automatic closing of the eyelids, and thus imitate the spontaneous brain-action of blinking the eyelids in consequence of a flash of light. To physiologists this analogy may be suggestive regarding the important natural functions of the human frame.

 

Effect of Alcohol on Brain-Substance.—When brain-substance is placed in alcohol, it loses its water and its mobility of particles, and becomes more solid and firm. The question here arises, Is this thing possible with the living brain? Is it possible that, in cases of delirium tremens, so much alcohol has been consumed as, by its diffusion through the brain, it has robbed nerve matter of its mobile character, and consequently of its power to throw off the products of its life-functions? That alcohol may, in this way, act upon the brain of the inebriate, is an opinion which, as yet, can hardly be demonstrated directly; but an experiment made by Mr. Charles T. Kingzett seems to render it highly probable. He places in a dilute solution of alcohol pieces of brain-substance derived from the ox, at the temperature of the blood, viz., 100° Fahr. At this temperature it is digested for some hours, and the liquid is then filtered. On cooling, the filtrate throws down a white deposit of matter which the alcohol has dissolved—a phenomenon which would seem to indicate some actual truth in Shakespeare's words, " O that men should put an enemy in their mouths to steal away their brains!"

 

Foray of an Army of Ants.—A writer in Land and Water gives an interesting account of a foray by an army of ants, which he witnessed in South Africa. This army, estimated to number about 14,000 ants, started from their home in the mud walls of a hut, and marched out in the direction of a small mound of fresh earth in the vicinity. The head of the column halted on reaching the foot of the mound, and the remainder of the force did likewise till the entire army was assembled. Then the forces were divided: one part remained at the foot of the mound and ran round and round it; the rest mounted to the top, and some of them entered the loose earth and speedily returned, each bearing a young grasshopper or cricket, dead, which he deposited upon the ground and returned for a fresh load. Those who had remained on the outside of the mound took up the crickets as they were brought out of the earth, and bore them down to the base of the hill, returning for a fresh load. Soon the contents of the mound seemed to be exhausted, and then the whole force returned home, each carrying his burden of food for the community. Here was a regular foray, planned and executed with military precision, the country surveyed, and the depot of provisions known accurately before the march was made; at the mound, prudential division of labor, and care taken that none of the victims should escape.

 

Remedy for Cold in the Head.—Dr. David Ferrier, having used with great success trisnitrate of bismuth to cure "cold in the head," sends to the Lancet a communication in which he warmly commends the employment of bismuth, either alone or in conjunction with other drugs, in the treatment of nasal catarrh. Bismuth of itself being heavy, and difficult to inhale, it is advisable, he writes, to combine it with acacia-powder, which increases the bulk, and renders the powder more easily inhaled, while the secretion of the nostrils causes the formation of an adherent mucilaginous coating, of itself a great sedative of an irritated surface. The sedative effect is greatly strengthened by the addition of hydrochlorate of morphia, which speedily allays the feeling of irritation and aids in stopping the reflex secretion of tears. He proposes the following formula: Hydrochlorate of morphia, two grains; acacia-powder, two drachms; trinitrate of bismuth, six drachms. Of this powder one-quarter or one-half may be taken as snuff in the course of twenty-four hours. The inhalations should be commenced as soon as the symptoms of catarrh begin to show themselves, and should be used frequently at first, so as to keep the interior of the nostrils constantly well coated. The powder checks the flow of mucus, and stops the sneezing. It causes scarcely any perceptible sensation. A slight smarting may occur if the mucous membrane is much irritated and inflamed, but it rapidly disappears. After a few sniffs of the powder, a perceptible amelioration of the symptoms ensues, and in the course of a few hours, the powder being inhaled from time to time, all the symptoms may have disappeared.

 

Evolution of the Horse.—Prof. Huxley devotes the sixth and last lecture of a course upon the origin of existing vertebrate animals to considering the evidences of the evolution of the horse. After tracing the genealogy of the horse from Orohippus, through Palæotherium, Hipparion, etc., to Equus, the author remarks as follows: "The evidence is conclusive as far as the fact of evolution is concerned, for it is preposterous to assume that each member of this perfect series of forms has been specially created; and if it can be proved, as the facts certainly do prove, that a complicated animal like the horse may have arisen by gradual modification of a lower and less specialized form, there is surely no reason to think that other animals have arisen in a different way. This case, moreover, is not isolated. Every new investigation into the Tertiary mammalian fauna brings fresh evidence, tending to show how the rhinoceros, the pigs, the ruminants, have come about. Similar light is being thrown on the origin of the carnivora, and also, in a less degree, on that of all the other groups of animals. It is not, however, to be expected that there should be, as yet, an answer to every difficulty, for we are only just beginning the study of biological facts from the evolutionary point of view. Still, when we look back twenty years to the publication of the 'Origin of Species,' we are filled with astonishment at the progress of our knowledge, and especially at the immense strides it has made in the region of paleontological research. The accurate information obtained in this department of science has put the fact of evolution beyond a doubt; formerly the great reproach to the theory was, that no support was lent to it by the geological history of living things; now, whatever happens, the fact remains that the hypothesis is founded on the firm basis of paleontological evidence."

 

Wood Pavements.—After a very thorough investigation of the advantages possessed by different kinds of pavements—granite, asphalt, and wood—the corporation of London has decided in favor of the last. The report of the city engineer shows that a horse traveling on a granite pavement may be expected to fall once for every one hundred and thirty-two miles traveled, on asphalt once in one hundred and ninety-one miles, and on wood once in four hundred and forty-six miles. The injury sustained by the animal is also far less serious from a fall upon wood than upon asphalt or upon granite. The mode of constructing wooden pavements in London appears to differ from that which has obtained in this country. The surface-water is kept out by means of a layer of asphalt, and there is a flooring of planks as a superstructure, which gives great elasticity, and by distributing the weight equally over a considerable area, adds to the power of endurance of the pavement. This decision of the London Corporation will occasion surprise on this side of the water, where wooden pavements have been pronounced an utter failure. It remains to be seen whether good material and careful construction will avail to remove the capital objection to wood as a material for pavements—its liability to speedy decay.

 

The Ice Age in Great Britain.—In a paper on the Ice age in Great Britain, R. Richardson cites facts with regard to the shallow depth of the ocean between Great Britain and Iceland and Greenland on the one side, and over the German Ocean on the other, and adduces reasons for holding that in the glacial era this region was terra firma; that the glaciers of Great Britain came over this emerged land from the north and west; and that the cold of the glacial era was due, in part at least, to the closing thus of the Arctic and exclusion of the Gulf Stream. The facts appear to symptoms of catarrh begin to show themselves, and should be used frequently at first, so as to keep the interior of the nostrils constantly well coated. The powder checks the flow of mucus, and stops the sneezing. It causes scarcely any perceptible sensation. A slight smarting may occur if the mucous membrane is much irritated and inflamed, but it rapidly disappears. After a few sniffs of the powder, a perceptible amelioration of the symptoms ensues, and in the course of a few hours, the powder being inhaled from time to time, all the symptoms may have disappeared.

 

Evolution of the Horse.—Prof. Huxley devotes the sixth and last lecture of a course upon the origin of existing vertebrate animals to considering the evidences of the evolution of the horse. After tracing the genealogy of the horse from Orohippus, through Palæotherium, Hipparion, etc., to Equus, the author remarks as follows: "The evidence is conclusive as far as the fact of evolution is concerned, for it is preposterous to assume that each member of this perfect series of forms has been specially created; and if it can be proved, as the facts certainly do prove, that a complicated animal like the horse may have arisen by gradual modification of a lower and less specialized form, there is surely no reason to think that other animals have arisen in a different way. This case, moreover, is not isolated. Every new investigation into the Tertiary mammalian fauna brings fresh evidence, tending to show how the rhinoceros, the pigs, the ruminants, have come about. Similar light is being thrown on the origin of the carnivora, and also, in a less degree, on that of all the other groups of animals. It is not, however, to be expected that there should be, as yet, an answer to every difficulty, for we are only just beginning the study of biological facts from the evolutionary point of view. Still, when we look back twenty years to the publication of the 'Origin of Species,' we are filled with astonishment at the progress of our knowledge, and especially at the immense strides it has made in the region of paleontological research. The accurate information obtained in this department of science has put the fact of evolution beyond a doubt; formerly the great reproach to the theory was, that no support was lent to it by the geological history of living things; now, whatever happens, the fact remains that the hypothesis is founded on the firm basis of paleontological evidence."

 

Wood Pavements.—After a very thorough investigation of the advantages possessed by different kinds of pavements—granite, asphalt, and wood—the corporation of London has decided in favor of the last. The report of the city engineer shows that a horse traveling on a granite pavement may be expected to fall once for every one hundred and thirty-two miles traveled, on asphalt once in one hundred and ninety-one miles, and on wood once in four hundred and forty-six miles. The injury sustained by the animal is also far less serious from a fall upon wood than upon asphalt or upon granite. The mode of constructing wooden pavements in London appears to differ from that which has obtained in this country. The surface-water is kept out by means of a layer of asphalt, and there is a flooring of planks as a superstructure, which gives great elasticity, and by distributing the weight equally over a considerable area, adds to the power of endurance of the pavement. This decision of the London Corporation will occasion surprise on this side of the water, where wooden pavements have been pronounced an utter failure. It remains to be seen whether good material and careful construction will avail to remove the capital objection to wood as a material for pavements—its liability to speedy decay.

 

The Ice Age in Great Britain.—In a paper on the Ice age in Great Britain, R. Richardson cites facts with regard to the shallow depth of the ocean between Great Britain and Iceland and Greenland on the one side, and over the German Ocean on the other, and adduces reasons for holding that in the glacial era this region was terra firma; that the glaciers of Great Britain came over this emerged land from the north and west; and that the cold of the glacial era was due, in part at least, to the closing thus of the Arctic and exclusion of the Gulf Stream. The facts appear to warrant these conclusions. We give them as stated briefly in the American Journal of Science:

"The depth between Britain and Iceland mostly does not exceed 100 fathoms, and nowhere exceeds 1,000; one tract of sea, extending in a straight line from the eastern coast of Greenland, via Iceland and Faroe, to Scotland, does not exceed 500 fathoms. The depth of the sea in the English Channel is only about 20 fathoms, and the average depth of the German Ocean is not over 40 fathoms. The depth between Britain and Greenland is small compared with the average depth of the Atlantic. According to the author, one of the oscillations of level, such as have occurred over the earth's surface, had the effect to unite Britain and Northern Europe with Greenland and the arctic regions, to give the polar ice-fields access to Europe, to divert the course of the Gulf Stream and free Northwestern Europe from its influence, and, in conjunction probably with some diminution in the influence of the sun, to produce a glacial epoch."
 

Pet Snakes.—Frank Buckland communicates to Land and Water a very interesting notice of "Cleo," a pet boa-constrictor. This animal was of the kind called "painted boa," and had come from Brazil. Its length was seven feet five inches, and its weight nine pounds. Cleo came into the possession of Mr. Mann, a friend of Mr. Buckland's, in 1870, and from that time till its death was his constant companion. Her food consisted of pigeons, of which she took on the average one a week. If a pigeon were offered to her when she was not hungry, she would take but little notice of it. If the two were left together for a while, they became friends. Neither pigeons nor any other animal ever showed any fear of this serpent.

She always "killed her bird" instantaneously, seizing it by the beak, and breaking its neck by a rapid movement. She never crushed her prey to death, but invariably waited to see that it was motionless before laying her coils upon it. The constricting power was reserved for mastication, and was very sufficient for that purpose.

"We have, in traveling," writes Mr. Mann, "carried her about with us, both in railway-carriages and hotels, unsuspected by others, and no amount of inconvenience or discomfort appeared to distress her so long as we were near. She thoroughly understood the joke of keeping concealed when strangers were present. It was only when we were alone, or with our own family, that she came forth of her own accord to join the conversation. She never avoided children, but would allow them to take liberties which she would never have borne from any other stranger. When offended in any way, she simply walked off to some inaccessible corner, and waited the departure of the offender.
"I do not remember any young child showing the slightest fear when Cleo came to make acquaintance.
"The manner of Cleo' s death was so much in accordance with her character that few of her friends will be surprised at what I have to tell.
"During last autumn I was laid up with a very serious illness. At first Cleo appeared to enjoy my being at home all day long, but soon began to understand, principally from my wife's anxiety, that there was something the matter, and she refused food. One night she came to my bed to talk to me as usual, but I was too ill to take any notice of her (indeed, I could neither move nor speak). She tried in vain to make me respond to her caresses, and, after a while, returned to her own bed, refused not only food, but water, and died within a day or two. To any one that knew her it was visible that she was suffering grief, as a dog is sometimes known to do under similar circumstances."
 

The Northerly Winds of California.—In a paper on the northerly winds of the great central valley of California, Mr. J. H. C. Bonte attributes to the prevalence of these winds the peculiar dry and moderately exhilarating climate of that region. Further, he asserts that without the north winds, and with the consequent increase of moist heat, the vegetation now cultivated in the valley would be crowded out by dense tropical growths. It is reasonable to believe that the desiccating power of the north wind, by preventing and dissipating the noxious exhalations of animal matter, acts as a preventive of disease. The north winds, following the rainy season, by drying and baking the soil, dissolve and pulverize its particles, thus freeing its productive powers. Fineness of fibre and concentrated nutriment are imparted to all the vegetable growths of the valley by the north wind, and it is possible that the grapes and strawberries of California may receive their delicate flavor from the same source. Cereal grains are made solid and flinty by this influence, and thus enabled to resist the damaging effects of moisture. The comparative exemption of the valley of California from the ravages of the weevil doubtless arises from the desiccating power of the north wind; and the same cause checks the growth of fungi. The economical value of the north wind is discernible in its power to preserve from rapid decay houses, barns, fences, etc., and the same influence must protect iron from destructive rusts.

 

Effects of Lightning on Different Species of Trees.—The effects of lightning on various species of trees have been made a subject of investigation by Daniel Colladon, who communicates to the Geneva Society of Natural History the results of his observations. He states that, when a poplar is struck, all the upper part of the tree remains perfectly sound and green. The height above the ground at which the injuries appear does not, in large poplars, exceed the third of the tree's height. These injuries commence immediately below the junction of the strong branches with the trunk. In general they do not reach quite to the ground. It is always the tallest poplar that is struck. In some cases the storm will pass over trees of other species, and will explode on poplars, though they be of less height. M. Colladon has never met with any traces of carbonization. The cases in which several poplars have been injured by a single discharge of lightning are rare. One such case is recorded by the author where three poplars were damaged by the same stroke. These trees stood in a straight line, and about twelve feet distant from each other.

 

How they teach Geology in Rome.—The eminent archaeologist, G. Mortillet, gives an amusing account of a class-lecture on geology which he once attended in the Roman University of the Sapienza. "I succeeded," he writes, "not without difficulty, in getting leave to be present at a lecture on geology. I was introduced into a large hall; in the middle stood a small table, at which four persons were seated. On the one side sat the professor in an arm-chair, and on the other three students in common chairs. Near the professor's seat was a more comfortable arm-chair for the inspecting prelate, who from time to time came to see that the teaching went on aright. As a stranger supposed to be well-disposed, I was honored with a seat in the grand armchair, I expected to listen to an interesting lecture in good Italian; the more, inasmuch as the professor, Ponzi, now a Senator of Italy, is a distinguished man, and a savant of repute. But I was disappointed. The professor, for upward of half the time of the lesson, was obliged to dictate—for such was the rule—his lecture, which had been written in advance in Latin, and revised and corrected by the censor. During the latter half he was permitted to give in Italian explanations of the dictated paragraphs; but he was not at liberty to diverge from his text, nor could the students take notes. These things I have seen with my own eyes at Rome under the reign of Pius IX., author of the 'Syllabus.' "

 

Effects of Compressed Air on Animals.—The mechanical effects of compressed air upon the animal economy, as ascertained by Bert, are to cause a lowering of the diaphragm and liver, and a consequent increased pulmonary vital capacity; this effect, while gradual in its production, lasts long after the subject is withdrawn from the compressed-air bath. Pravaz finds that the heart's action is at first increased, and then lessened, the pulse first becoming more rapid, and then slower, but never falling below the rate at normal pressure. The respirations are diminished during immersion, but on removal of the increased pressure they rise in frequency and in direct proportion to the degree of compression. There is an increase in the amount of urea excreted, but this increase diminishes the longer the sojourn in the compressed air. There is at the same time an increase in the amount of carbonic acid expired. The temperature of the body rises above the normal at first, and then falls as the immersion is prolonged. These varying effects are due, Pravaz thinks, to the two influences of inward atmospheric pressure and hyper-oxygenation, the former tending to diminish the circulation and the organic changes, and the other to increase them.

 

Occurrence of Nickel-Ores.—Nickel-ores occur in great abundance in New Caledonia, and are being actively worked. These ores in no way resemble those from which nickel has hitherto been extracted, being silicates of nickel and magnesia, while the others are arsenio-sulphurets. They are found in serpentine rocks, which are very abundant in various parts of the island, associated with diorites, amphibolites, etc. Sometimes they appear on the various rocks as a beautiful green coating; sometimes they penetrate the rocks, giving them a more or less intense color; sometimes they form therein threads, which may assume the importance and regularity of veins; and sometimes, again, they occur in pockets. As might have been expected, the nickel is associated with iron, chrome, and cobalt, these metals, especially the two former, being very abundant; their stratification is analogous to that of nickel, except where cobalt is met with. The latter metal is associated with manganese, forming pure masses, of greater or less extent, in the midst of friable arenaceous rocks, composed of feldspathic and magnesian detritus.

 

Age of Trees in Relation to Time of Leafing.—In the course of a discussion, in the Paris Académie des Sciences, of the question whether the annual buds of a tree, as it grows old, preserve the characters of youth or share in the old age of the individual which produces them, it was stated that, according to observations made by Prof. Decaisne on the Robinia pseudacacia (common locust) of the Muséum d'Histoire Naturelle, the time of leafing does not vary with age. At Pisa, results a little different were obtained; there the gingko (Salisburia adiantifolia) and the walnut have been found to produce their leaves earlier in the season from year to year as they have advanced in age. On the contrary, the Æsculus hippocastanum, or horse-chestnut, is more tardy in proportion as it grows older. M. de Candolle, who was present at the meeting of the Academy, quoted observations carefully made every year since 1808 on two chestnut-trees at Geneva; these trees have leaved invariably between the ninety-third and the ninety-sixth day of the year. He further quoted the instance of a vine growing at Ostend. This vine has been observed during thirty-three years, and during the first eleven years it leaved on the one hundred and twenty-seventh day of the year; in the second period of eleven years, on the one hundred and twentieth; in the third, on the one hundred and sixth. Thus there would 'seem to be a continuous progression, the vine becoming more precocious in proportion to its advance in age.

 

Effects of Electricity on Particles suspended in Liquids.—Some interesting observations by Holtz on the effects of electricity on particles suspended in liquids are recorded in Poggendorff's Annalen. In giving an account of these observations, Holtz remarks that the "migration" of particles suspended in a liquid, subjected to electric currents, has long been known, and was thoroughly investigated by Quincke. But in all cases of such motion Holtz finds that there is, at the same time, a clinging of particles to one of the poles. This is sometimes so evident that one might construct an electroscope on this principle for ascertaining the polarity. Especially notable is the tendency of semen lycopodii in insulating liquids, particularly sulphuric ether, to cover the negative pole with a thick coating; while sulphur, cinnabar, or sulphide of antimony, in the same liquid, only coats the positive pole. A simple medicine-glass suffices for the experiment, a conductor or half-conductor being introduced through the stopper. The glass is held in the hand, and the conductor brought to an electric machine; the phenomenon then occurs. It is better, of course, to have the bottom perforated for insertion of the second pole, or to use an open glass, with the two poles pushed down into it. Either a frictional or an influence machine may be used.

 

Have Bees a Sense of Hearing?—Though the best observers deny to bees the possession of a sense of hearing, a writer in Newman's Entomologist relates an instance in which a hive of bees appear to have heard the summons of their queen. A swarm of bees had been gathered into a hive, which was allowed temporarily to rest upon a table. On lifting the hive, in order to set it upon the hive-board, the portion of the table on which the hive had stood was found to be covered with bees, which soon began to run about, from their having been suddenly disturbed. The hive was now placed on the hive-board, with the entrance toward the bees. For a little while they continued to run about, as if bewildered, but then was heard a peculiar vibrating and buzzing sound proceeding from the hive. In an instant all the bees faced about, with their heads toward the hive, and all marched into it in regular procession.

 

A New Respirator.—A new mask for filtering dust out of the atmosphere, and intended for use by workmen who follow sundry unhealthy trades, has been devised by Dr. B. W. Richardson. Having tried various substances in order to find a good filter, he gives the preference to feathers. The advantages of feathers as filters of dust are many: they are light, they separate perfectly, admitting air in any quantity while excluding dust, and they absorb water less perhaps than any other porous flexible substance. They have the further advantage of being cheap, and of being easily made up into filters. In constructing his mask he connects the light feathers drawn from the leg-plumage of the pheasant along a line of tape. This band he wraps around the perforated breathing-tube of the mask, so that the feathers fall over the perforations. In inspiration the feathers come down over the perforations, filtering the air as it enters, while in expiration they are blown out from the tube as feather-valves.

 

Bat-Guano.—In reply to a circular of inquiry addressed to numerous correspondents in the Southern States, Mr. McMurtrie, chemist to the United States Department of Agriculture, received a number of letters describing deposits of "bat-guano." Near Georgetown, Williamson County, Texas, there is a deposit supposed to amount to hundreds of tons, many apartments in the cave in which the excrement is found being filled to the mouth. Near Tuscumbia, Alabama, is a deposit estimated to be worth $20,000. A cave near San Antonio, Texas, is supposed to contain 15,000 or 20,000 tons of this guano, and the store is annually increasing. Samples from these and other deposits have been analyzed by Mr. McMurtrie. Most of them he found to contain both ammonia and nitrates. Under the microscope the material is seen to consist of the remains of the hard parts of insects in a finely-comminuted condition, which are the source of its nitrogenous constituents. As a fertilizer this guano compares favorably with the fish-products manufactured in New England, and even with Peruvian guano.

 

Prof. Marsh and his Paleontological Work.—Prof. O. C. Marsh, in a lecture to the graduating class of Yale College, summed up the main results of his paleontological researches in the Rocky Mountains. A syllabus of the lecture is published in the American Journal of Science. His conclusions as to the size and growth of the brain in mammals, from the beginning of the Tertiary to the present time, may be briefly stated thus: 1. All tertiary mammals had small brains. 2. There was a gradual increase in the size of the brain during this period. 3. This increase was mainly confined to the cerebral hemispheres. 4. In some groups the convolutions of the brain have gradually become more complicated. 5. In some the cerebellum and olfactory lobes have even diminished in size. There is some evidence that the same law of brain-growth holds good for birds and reptiles from the Cretaceous to the present time. Some additional conclusions in regard to American tertiary mammals as far as now known are as follows: 1. All the ungulata from the eocene and miocene had upper and lower incisors. 2. All eocene and miocene mammals had separate scaphoid and lunar bones. 3. All mammals from these formations had separate metapodial bones. At the conclusion of the lecture Prof. Marsh announced that his work in the field was essentially completed, and that all the fossil remains collected and in part described were now in the Yale College Museum. In future he should devote himself to their study and full description, and he hoped at no distant day to make public the complete results.

 

Seed-Production of the Sugar-Beet.—From experiments made by Corenwinder, it appears that when beet-roots are planted for the sake of seed, they, on first sprouting, part with a certain quantity of their sugar, which goes to support the young leaves. From this time forward until the moment when the rudiments of the seeds appear, the sugar remains in the root. Hence it would appear that the carbon requisite for the formation of the stems and leaves, which during this period attain a great development, comes mostly, if not entirely, from the atmosphere. From the time when the seeds appear, the sugar in the root disappears rapidly, and when the seed is fully ripe there is no more left.

 

The Kauri Pine.—The kauri pine is one of the chief timber-trees of New Zealand. These trees in some instances have been found fifteen feet in diameter and one hundred and fifty feet in height. In some kauri trees the wood is prettily marked or mottled, and is in great demand for cabinetmaking. The timber is also valuable for ship-building. The kauri does not grow farther south than latitude 37° 30'. The gum which exudes from this tree is an article of commerce. Over a large area of land which has been exhausted by kauri forests in past ages, and is now barren, the gum which has exuded from the dead trees is found at a depth of from two to three feet. This gum is valuable in the manufacture of varnish. During the years 1870, 1871, and 1872, no less than 14,276 tons of the gum were exported, amounting in value to nearly half a million pounds sterling. The Maoris bring a considerable quantity to market, and the proceeds thus obtained enable them to procure the comforts of dress and living to which they have now become accustomed.

 

An Important Sanitary Fact.—The following interesting statement is made by Dr. Littlejohn, Medical Officer of Health for Edinburgh: "Edinburgh consists of two distinct towns, an old and a new, but with very different populations. The new town is inhabited by the better classes, and is preeminently a water-closet town; whereas the old town consists for the most part of overcrowded tenements, in which pails are used for the reception of excreta. These pails are brought to the street daily and emptied into carts provided by the authorities. Considering the low morality of the population, the bad ventilation, the overcrowding, and the retention of the filth in the living-rooms for the greater part of the day, it might naturally have been supposed that typhoid and diphtheria would be endemic in the old town. This is not the case, however, for, despite the surrounding conditions, these diseases may be said to be practically unknown. But in the new and water-closeted town the case is quite different: typhoid and diphtheria are never entirely absent, are frequently epidemic, and it has been noticed that the ravages of these diseases have been greatest in the best houses. The lesson which this teaches is, that any system of removal cannot be sanitary unless all the excremental produce of a population is so promptly and so thoroughly removed that the inhabited place, in its air and soil, shall be absolutely without fecal impurities."

 

Utilization of Sewage in England.—Down to the year 1874 the sewage of the English town of Coventry (population 40,000) was cast into the river Sherbourne in an undefecated state. It rendered the stream black and disgusting, and a terrible nuisance to the neighborhood, as well as a great source of danger to health, inasmuch as the sewage, at a few miles distance, found its way into the source of the water-supply of the town of Warwick. But, by the erection of sewage-works, all this has since been remedied, and the river Sherbourne has been so purified that fishes have returned to its waters. In selecting a site for the works, advantage was taken of a fall of six feet in the nature of the ground, so as to avoid the costly expedient of pumping the sewage, and to work it throughout by gravitation. A narrow strip of comparatively valueless land along the river-bank, about thirteen acres in extent, was thoroughly drained and embanked against the rising of the river during floods. The sewage is here subjected to four processes, viz.: 1. Straining by means of mechanical strainers, thus removing the solids, which form a rich manure. 2. Chemical treatment by sulphate of alumina and milk of lime, and precipitation. 3. Filtering of the effluent water by percolation through a depth of five feet of earth. 4. Drying of the precipitate or sludge in the precipitating tanks. The cost of purifying the entire sewage of Coventry in this way, including rent of land and interest on capital, and without deducting receipts from the sale of manure, is about 1s. 7d. per head of the population per year. But, taking into account the chemical value of the manure, the cost would be about twopence per head.

 

Construction of Water-Tanks.—A water-tank at the top of St. George's Hospital, in London, recently burst, inundating the wards and causing destruction of life and property. This tank, which held about thirty-four tons of water, was made of cast-iron plates half an inch thick, bolted together in the usual way; in form it was a square of ten feet on a side and the depth twelve feet. The thickness of the iron plates was adequate to resist the strain put upon them only on the usual condition of the employment of tie-bars and nuts of the needed strength. But, instead of adopting the proper plan of bolting these tie-bars directly to the flanges by which the plates themselves were bolted together, thin plates of wrought-iron, only one-quarter of an inch thick, were bolted to these flanges, and the tie-bars were attached to cross-pieces that ran through holes in these plates. The cross-pieces were so short that on the least disturbance one end might slip out of its place, leaving the entire stress on the other end and on the thin plates in which it rested. As was to be expected, the plates gradually rusted, and, when the corrosion had advanced so far as to allow the bolt to be torn away by that strain on the sides of the tank which the cross-bars were intended to resist, the tank tore in two, and the water made its escape.

 

Movements of "Cold Waves."—Prof. Loomis, of Yale College, contributes to the American Journal of Science and Arts, for July, the fifth of his valuable series of papers on "Meteorology."

In a former paper he presented facts showing the origin and probable cause of extremely low temperatures. It was found that they developed among the Rocky Mountains, and moved thence, as "cold waves," over the continent eastward. Since the publication of that paper this phenomenon has become well understood, and is now sustained by further proof. It appears that low temperatures follow in the wake of storms; or, in other words, areas of high barometer follow those of low barometer.

By low temperature is understood a degree of cold which is greatly below the mean temperature of the place or area where it prevails. Thus the cold wave of December, 1872, started in Dakota on the 16th, and the temperature fell to 15°, 25°, and finally 44°, below the mean of the month. At the same time the barometer rose to 30.64.

The cold wave moved eastward and southeastward, the barometer rising as the cold came on. The cold was extreme from the Rocky Mountains to Lake Michigan, and from latitude 38° to the British possessions.

In New York, during the last six days of the month, the depression of temperature ranged from 18° to 24° below the mean of the month.

It is quite obvious, Prof. Loomis observes, that the cold experienced in Dakota did not come from beyond the Rocky Mountains, but on the easterly side, near longitude 100°. The greatest observed cold in the instance referred to was not at the most northern stations, which strengthens the conclusion expressed in a former paper that there is a source of cold independent of the transfer of air from a higher to lower latitudes. As the cold wave moves eastward, the intensity of the cold is found to diminish.

The professor calls attention to the very interesting fact that, during the low temperature of December, 1872, the stratum of cold air was of no great thickness, probably not more than 9,000 feet, as was shown at Mount Washington. On the 26th of the month, when the cold was at its maximum over the region, it was found that the temperature was higher by 20° Fahr. at the summit of the mountain than at its base.

Further facts are presented in this paper, showing the general form of areas of low barometer and of high barometer. It was previously shown that a storm area is more or less oblong, and not in any observed case entirely circular. The same appears to be true of the cold areas.

To illustrate this a chart is given, on which lines of equal barometric pressure are drawn, the lines of highest pressure being at and near the centre of the area, but diminishing as the distance from the centre is increased. These areas have a long and a short diameter, the one being in some cases twice or thrice that of the other.

The relation of barometric pressure to rainfall receives further attention in the present paper, and the conclusions previously arrived at are fully sustained.

The rainfall is greatest while the barometric pressure at the centre of the storm is diminishing, or the storm increases in intensity while the barometer continues to fall; and, on the other hand, the storm diminishes in intensity while the barometer at the centre of the storm is rising.

The progressive movement of storms seems to be sometimes interrupted, and they remain stationary over a section of country for some days. This occurs off the coast of Newfoundland, and the cause of it is attributed to unusual precipitation of vapor. In that region the rainfall is about fifty-six inches in a year, while at two hundred miles from the coast it is only forty inches.

 

Preservation of Entomological Specimens.—M. Felix Plateau having recommended the use of yellow glass in the windows of rooms containing entomological collections, as a means of preserving intact the natural colors of the specimens, M. Capronnier, of the Entomological Society of Belgium, made some experiments to determine the value of this suggestion. He made five small, square boxes, each covered with a pane of yellow, violet, green, blue, or colorless glass. He then fixed in the middle of each box one of the inferior wings of Euchelia Jacobeæ, which are of a deep carmine color, uniform in tone. Each wing was partly covered with a band of black paper, and their position was so arranged as to leave exposed successively each of the parts during a period of fifteen, thirty, and ninety days. The result was as follows: Colorless Glass.—The carmine tint visibly attacked after exposure of fifteen days; alteration more sensible after thirty days; after ninety days the carmine had passed into a yellowish tint. Blue.—The same results as with colorless glass. Green.—A change indicated on the thirtieth day; on the ninetieth the alteration was marked. Yellow.—After ninety days the carmine color almost intact. M. Capronnier accordingly concludes that a yellowish color should be preferred in every arrangement of an entomological room.

 

Anti-Vivisection Legislation.—In commenting upon the bill for regulating the practice of vivisection in England, Iron remarks upon the absurdity of a Parliament of sportsmen, supported by a mob out-of-doors, passing such a law. "Either of them" (sportsmen or mob) "for the mere pleasure of killing, or in the treatment of domestic animals, inflicts more unnecessary pain on the animal creation in one day than the whole body of physiological inquirers do in a year. The physiological worker will, if this bill passes, have to pursue his unrequited labors under the supervision of a policeman, and with a ticket-of-leave; and the result will be that original, unremunerated research of a most important class will not only continue to be pursued without endowment, but under the risk of penal servitude, the tournament of doves, pheasant-battues, and horse-racing, being all the while in full swing." A petition, signed by all the leading members of the medical profession, has been presented to the House of Lords, demanding certain modifications in the bill.

 

Meats cooked by Cold.—It is a fact of familiar experience that extreme cold produces in organic substances effects closely resembling those of heat. Thus, contact with frozen mercury gives the same sensation as contact with fire; and meat that has been exposed to a very low temperature assumes a condition like that produced by heat. This action of intense cold has been turned to account for economical uses by Dr. Sawiczevosky, an Hungarian chemist, as we learn from La Nature. He subjects flesh-meats to a temperature of minus 33° Fahr., and having thus "cooked them by cold," seals them hermetically in tin cans. The results are represented as being entirely satisfactory. The meat, when taken out of the cans a long time afterward, is found to be, as regards its appearance and its odor, in all respects as inviting as at first. It is partially cooked, and needs but little treatment more to prepare it for the table. A German government commission has made experiments with this process, and two naval vessels dispatched on a voyage of circumnavigation were provisioned with this kind of meat. An establishment has been set up in Hungary for preserving meats in this way.

 

Causes of Putrefaction and Fermentation. — A year or two ago, Dr. J. Dougall, of Glasgow, at the Social Science Congress, held in that city, announced, as the result of investigations made by himself, that the presence of an alkali determines putrefaction in organic matter, while the presence of an acid determines fermentative changes. The same line of inquiry has been taken up since by Dr. John Day, of Victoria, Australia, who finds in Dougall's discovery an explanation of the presence in hospitals of septic poisons, giving rise to pyæmia, erysipelas, and puerperal fever. The Sanitary Journal, of Toronto, has a paper by Dr. Day upon this subject, the purport of which may be briefly stated as follows:

Hospitals, as usually constructed, have alkaline ceilings, alkaline walls, alkaline floors (owing to the use of soap in cleansing them). Experience has shown that pyæmia is of extremely infrequent occurrence in temporary hospitals consisting of rough wooden sheds. The incessant generation of peroxide of hydrogen by the turpentine of the wood doubtless prevents putrefactive changes, but, as turpentine always gives an acid reaction, this circumstance must greatly increase the disinfecting power of the peroxide, by determining the fermentative instead of the putrefactive decomposition of the pus-cells and other organic matter given off from the patient.

Dr. Day proposes the following method of counteracting the evils of hospital-life: The boards of the floor he would first cover with a coat consisting of equal parts of gasoline and boiled linseed-oil, to which is added a little benzoic acid. When dry, the surface is polished with a paste of beeswax, turpentine, and benzoic acid. Boards so prepared are, in his opinion, rendered permanently disinfectant. The walls and ceilings might be rubbed smooth, and coated with a varnish of paraffine or oil of turpentine; or, better still, they might be coated with silicate paint, then rubbed down and varnished. For the purpose of keeping the air pure, and destroying the pus-cells floating in it, he recommends, in addition to ventilation, the use of certain volatile substances, such as gasoline, benzine, and eucalyptus oil. The furniture should be occasionally brushed over with either gasoline or benzine, in which a little benzoic acid has been dissolved.

 

Cultivation of Caoutchouc-yielding Trees. — In 1870 Mr. Clements R. Markham advocated the planting of caoutchouc-yielding trees in India, and in 1873 the first attempts were made, but without success, in the Darjiling Terai and in the district of Goalpara, Assam. In the following year two plantations were made in the Kamrup district of Assam and at Charduar, at the foot of the Himalayas, in the Durrung district. The latter plantation now covers 180 acres, and in 1875 there were in it 16,401 live cuttings. The species here cultivated is the native Ficus elastica. Several plants of the castilloa tree of South America are now in a very flourishing condition at Kew Gardens, and a good supply of this species has been thence forwarded to India, where they will form the nucleus of extensive plantations. In June of the present year an agent was to have been sent out to Brazil to collect healthy young plants of the hevea, the tree which yields the famous Pará India-rubber. Thus provision will be effectually made against the extinction of these valuable species of plants.

 

Inspecting Railways by Machinery. — Attached to the rear of the paymaster's car on the Pennsylvania Railroad, says the American Manufacturer, is an apparatus which it is thought will work much more satisfactorily than the telegraphic instruments formerly used by the officers while making their tours of inspection. A roll of white paper, 700 feet in length, encircles a cylinder, from which it is paid out at the rate of three feet to the mile run by the car, its forward movement being regulated by the revolutions of the nearest axle under the car. A lead-pencil placed about the centre of the paper indicates by its mark the condition of the track. The more uneven the track the longer will be the mark made by the pencil. Another way of showing the inspecting party that the track is uneven is by an horizontal piece of iron or steel, which oscillates like the pendulum of a clock as the train moves. When a very defective point is reached, the pendulum comes in contact with a metal on each side, circular in shape, which gives a sound like a bell.

 

Physiological Action of Coca.—The physiological action of the leaves of coca or cuca {Erythroxylon coca), a plant indigenous to Peru, has been the subject of much discussion lately in England. Sir Robert Christison, whose reference to the peculiar properties of this plant, in his address to the Edinburgh Botanical Society last November, gave rise to the discussion, has since taken up the subject again, in a paper read before the same society. The author gives an account of experiments made by himself and by fourteen other observers, under his instructions, with a view to determine the physiological action of coca and its principle, cocaine. His conclusions are that—1. When taken in quantities of two drachms by healthy persons it has no unpleasant, injurious, or suspicious effect whatever; 2. In a very few cases this dose of an inferior sample had no effect at all; 3. In by far the greater number of instances, and with a fine sample, extreme fatigue was removed and prevented from returning; 4. It does not in the end impair the appetite or digestion, although hunger, even after long fasting, is taken away for an hour or two; 5. The use of it is incompatible with the use of alcoholic liquors, except when the latter are taken in very small quantities.