Popular Science Monthly/Volume 15/July 1879/Popular Miscellany

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Popular Science Monthly Volume 15 July 1879  (1879) 
Popular Miscellany
 

POPULAR MISCELLANY.

Well-Water and Typhoid Fever.—In the summer of 1878 some forty persons in Rochester, whose supply of drinking-water was derived from a certain well, were taken sick with typhoid fever and other zymotic diseases. The health officer had the well closed, so that the people had to get water from other sources. Their recovery was rapid from that moment. A request was then addressed to all the physicians in the city to report the names and residences of all persons sick with typhoid fever. About fifty cases having been reported, health inspectors were sent to the various localities, who inquired into their sanitary conditions, the distance of cesspools, sewers, and privy-vaults from the wells; also whether the patients drank well-water either at their homes or at their places of business. Samples of water were taken from the wells, and submitted for analysis to Dr. Lattimore, Professor of Chemistry in the University of Rochester. The result of the inquiries was to show that, of the whole number of cases of typhoid reported, all but two had followed from the use of well-water; the exceptional cases arose from ill-ventilated apartments in close proximity to foul water-closets. It was also ascertained that a very large number of the wells in the city were situated within an average distance of less than thirty feet from cesspools and privy-vaults, while a great many were distant from them not over ten feet! In Professor Lattimore's report occurs one passage which must be quoted in extenso, namely, the one in which he remarks on the significance of the presence of common salt in well-water: "I would direct your special attention to the second column" [of his table showing the amount of solid matters in the water]," which shows the number of grains of common salt per gallon of water. No single indication is of so great sanitary importance in judging of the purity or impurity, and consequently of the safety or danger, of any water. How a substance, which is in itself not only harmless, but by most persons considered indispensable as an article of diet, becomes to the sanitarian a signal of danger in well-water, will be easily rendered apparent. No mineral substance is perhaps so universally diffused as common salt. It exists in the air, hence in all rain-water; in all soils, hence in all well or spring-water, though often in quantities too minute to be weighed upon the chemist's balance, as is the case in the Hemlock Lake water of this city. Salt being remarkably soluble, it is constantly being washed out of the soil into the streams, and ultimately carried down to its great reservoir, the ocean. We may, therefore, expect to find salt present in all ordinary well-water. What might fairly be considered as the average proportion for uncontaminated well-water in Rochester can be only estimated, but it certainly can not be large. Rivers may derive large quantities of salt from the drainage of manufacturing establishments upon their banks, but wells are not usually thus affected. Therefore, whenever, in well-water, it rises above a very few grains per gallon, it becomes certain that it comes from some other source than the soil. What is that source? A moment's reflection will convince any one that nearly all the salt used for domestic purposes escapes by the way of two channels—the water-closet and the house-drain. Therefore, we should expect, what is always found on examination to be true, that whatever sewage may or may not contain, it always contains salt."

 

Improved Diaphragm for the Phonograph.—Messrs. Preece and Stroh exhibited at a recent meeting of the London Royal Society a new form of diaphragm, which intensifies the loudness and removes some of the imperfections of the present disk of the phonograph. They had sought for a diaphragm which should give all the finest shades of sonorous vibrations, and, after trying many substances, a stretched membrane of thin India-rubber, rendered rigid by a cone of paper, was found to give the best effects. Messrs. Preeee and Stroh also exhibited a machine for tracing curves of the composite character which represent the sounds of speech, especially the vowel sounds. By this machine they are able to build up curves by putting together their constituent parts, and thus to study the various theories with regard to vowel-sounds which have been put forward. Several instruments were shown by which the vowel sounds were reproduced with more or less exactitude by vibrating a disk in accordance with the curves formed by the curve machine. One of them makes a simple and good siren, reliable for measurements, and gives promise of introducing a new musical machine which will give sweet sounds by the mechanical vibration of a disk. Though the knowledge of vowel-sounds is far from complete, Helmholtz's theory has been fully confirmed by the work the authors have done. The sounds can not, however, be, they say, exactly reproduced by mechanical means at present. Some interesting experiments were made on the loudness of sound, tending to show, it was urged, that sufficient importance has not been attached to the quantity of air thrown into vibration. Disks of different diameter, though vibrated with the same amplitude and pitch, increase in loudness very largely with the increasing dimensions of the disk.

 

A Large Terrestrial Globe.—A New York artificer, Grube, has constructed what purports to be the largest globe of the earth now in existence, showing all the prominent features of its surface. Its diameter is four feet and about one inch, the scale being one to 10,000,000. The range of even the Himalayas would not be visible upon this globe if the same scale were adopted for the elevations as for the map, and accordingly the relief is made upon a scale which exaggerates heights twenty times. The oceans, seas, and rivers are colored blue; the continents are yellow; the glaciers, icebergs and floating cakes of ice, white. Plains and mountain ranges are clearly shown, and every part of the world is exhibited in its true character. Red, black, and white lines cross the globe to indicate the isothermal belts, the variations of the magnetic needle, the date line where ships correct their logs by skipping from Saturday to Monday, and vice versa, and other facts of like character. The map has been corrected in the light of the latest discoveries. The northern coast of Siberia has been much altered in the atlases by the Nordenskjöld Expedition, the ships sailing in deep water over places marked as 500 miles inland, and being compelled to go hundreds of miles around promontories, etc., which are occupied on the maps by bodies of water. The globe is made of wood; the relief is formed by wax. Mr. Grube has been two years in perfecting his globe.

 

Is the "Uniformity System" an American Idea?—Among the many mechanical geniuses who by their inventions have helped to develop the manufacturing industries of the United States, none is entitled to higher rank than Thomas Blanchard, inventor of the tack-making machine, the machine for turning gun-stocks, that for making shoe lasts, of an improved process for bending timber, and of many other mechanical contrivances. An interesting sketch of Blanchard's life, written by Asa H. Waters, has recently been published for the purpose of vindicating for Blanchard his just place among American worthies, refused to him by certain historians of our national industries. Mr. Waters's pamphlet is a valuable contribution to the literature of invention, but he is certainly in error when he claims for Blanchard the credit of having originated what is known as the "uniformity system" in manufacture—the idea of making any number of perfectly uniform copies of the several parts of a piece of mechanism so that one copy may be interchanged with any other copy of the same part.

The origination of this idea is asserted by the author for Blanchard in the following terms: "This perfect uniformity of Blanchard's work" (with the gun-stock-turning machine) "suggested the idea of having all the parts of the guns made at the armories perfectly uniform, so as to be interchangeable" (p. 9). Again, same page:

"The War Department, impressed with the importance of having the guns so made that after a battle the broken ones could be readjusted, ordered the Springfield Armory to make all the parts interchangeable. After two years' effort the thing was accomplished. Lettering and numbering were abolished; all the component parts, even of the lock, were got out in large numbers, and thrown together indiscriminately. Thus was inaugurated the ' uniformity system ' so called. . . . It is not claimed that the whole credit of the 'uniformity system' should be given to Blanchard. . . . But to Blanchard belongs the credit of being its forerunner and suggester." And in a letter from Mr. Waters to us this system is declared to be "wholly of American origin," and he adds that in Europe it is known as "the American system."

Now, that the practical execution of the uniformity system was facilitated by Blanchard's invention is readily admitted; but the idea itself, and the execution of it, on a small scale, belong to an earlier period, and to another country. The all-sufficient proof of this is found in the following letter, written from Paris, under the date of August 30, 1785. The writer of this letter, Thomas Jefferson, addressing John Jay, says: "An improvement is made here in the construction of muskets. . . . It consists in making every part of them so exactly alike that what belongs to any one may be used for every other musket in the magazine. The Government. . . . is establishing a large manufactory for the purpose of putting it into execution. As yet the inventor has only completed the lock of the musket on this plan. He will proceed immediately to have the barrel, stock, and other parts, executed in the same way. The workman. . . . presented me the parts of fifty locks taken to pieces and arranged in compartments. I put several together myself, taking pieces at hazard as they came to hand, and they fitted in the most perfect manner." The letter will be found in the "Writings of Thomas Jefferson."

 

Insanity in Russia.—The ratio of insane persons to the whole population is extraordinarily high in Russia, namely, as 1 to 450. The causes of this have been investigated by Dr. Finkelburg, member of the Public Health Commission, and he has made it the subject of a lecture. Among the working classes he observes that the lack of physical and intellectual education, insufficient food, unhealthy dwellings, and a certain indolence of mind, contribute partly to the evil. But it is chiefly the abuse of alcoholic liquors that fills the lunatic asylums as well as the prisons. In the former drunkards figure to the extent of a fifth; in the prisons they constitute two fifths. With regard to educated people, the causes of their insanity are naturally very different, and they often date from the' earliest education. Children do not, in general, get as much rest as they absolutely need. That a child work diligently, keep its place in class, or quickly advance in the school grades, is all that is demanded, and people do not trouble themselves in the least as to whether the young and tender brain, kept in incessant activity, may not suddenly stop in its functions or its growth. Rousseau insisted on a purely negative education till twelve years of age, and in this he was wiser than our schoolmasters. The child that has lived in the open air to this age without contracting bad habits will have greater force of apprehension and will progress more rapidly than another who has been fatigued by premature work. Among adults, Professor Finkelburg distinguishes two great classes—men of work and men of pleasure. Continual activity and the suitable exercise of all the faculties are necessary to the preservation of intellectual and physical health, for it is the idlers that furnish the greatest number of hypochondriacs. But there is the excess of the overworked man, who is liable to mental maladies arising from fatigue of mind, joined with material cares, absence of sleep, emotions and agitations caused by a goal always imagined but never reached. Professor Finkelburg concluded by urging that every man should try as much as possible to vary his occupations, whatever they be, to give his tired mind agreeable recreation, to take walks regularly in the open air, etc., in order to restore the equilibrium of functions of body and mind.

 

Survival of Superstitious Beliefs.—Here are a few illustrations of the persistence of superstitious beliefs. They are taken from a paper in "All the Year Round," entitled "Some Popular Cures." Many, if not all of these beliefs, doubtless survive even on this side of the Atlantic. A cure for whooping-cough, in use not only in England but in North Germany, consists in putting into the mouth of the whooping child a newly-caught fish, and then letting it go again. The cough is communicated to the fish. Another cure for the same malady consists in passing the child nine times under and over a donkey. To charm away warts, an elder-shoot is to be rubbed over them; then as many notches are cut on the twig as there are warts. The twig is buried, and as it rots away the warts disappear. There are persons still living who have been stroked by a hanged man's hand for the sake of dispelling tumors. In Devonshire there is a superstition that, if a person suffering from any disease throw a handkerchief in the coffin of a suicide, the disease will be cured as the handkerchief rots away. In other localities, the fore-foot of a hare, worn constantly in the pocket, is considered a potent charm against rheumatism. A like practice is found in this country, a horse chestnut taking the place of the hare's foot. In some places the anti-rheumatic talisman is a potato. Bread baked on "Good Friday" is supposed to possess wonderful curative virtues. Such bread, it seems, never grows moldy. It is often kept for years, sometimes as many as twenty. It is most effectual when taken grated in brandy. Nor is it only for man's ailments that Good Friday bread is medicine; it is also considered good for some of the complaints of animals—for instance, it cures "the scours" in calves.

 

Climate at Great Altitudes.—The "Little Annie gold mine," in Rio Grande County, Colorado, is doubtless the highest gold mine worked anywhere on the globe, its elevation being 11,300 feet above sea-level. An interesting account of the climatic conditions lure existing is given by Professor C. E. Robins, in the "Kansas City Review of Science." The geographical position of the camp is 37° 28' 18" north, and longitude 106° 30' west—that is to say, it is in the latitude of Syracuse, the most southerly city of Europe; but, owing to the elevation, the climate is arctic. The mean annual temperature in 1877-'78 was 26·95° Fahr., the maximum being 69° (July), and the minimum-24° (November). The mean maximum was 50·4°, and the mean minimum 4·58° for the twelve months. Snow fell every month except July, 1877; few nights are without frost; the fall of snow is about twenty-four feet per year. The dry atmosphere is scarcely ever chilly. Even when the temperature is as low as-10°, the air is generally still. From the middle of November to the middle of June locomotion is performed on snow-shoes—runners of the Norwegian pattern. Absolutely cloudless days are very common. On the 11th, 12th, and 13th of August, the sun, moon, and several stars were visible from 10 a. m. to 2 p. m. Of a lunar rainbow, seen on the evening of August 4th, the same year, Professor Robins says that "it appeared about 9 p. m., the moon being full; and it lasted fifteen minutes. The chromatic scale was complete in the primary, and the secondary arc was perfectly defined around the entire semicircle. The upper outlines of the mountains were but faintly discovered through the blackness of the storm, while the valley of the North Alamosa was flooded under the arch by an inundation of intense light, brighter than that under the most brilliant aurora, but golden." Of parhelia there are about half a dozen striking exhibitions every year. Meteors are frequent, but the author has not observed either paraselence, aurora borealis, or mirage.

 

The Seeds of Disease.—It is believed by Pasteur that he has discovered the germs which produce puerperal fever and malignant pustule. The primary organism which engenders puerperal fever he describes as presenting itself in the form of cells united to each other in series of two, four, or six, and each having an average diameter of two thousandths of a millimetre. Of the researches which have resulted in the demonstration of the germs of malignant pustule we take the following account from the "Medical and Surgical Reporter": "M. Pasteur's researches on malignant pustule have proved to him that the disease was produced by the presence of the bacteridium discovered in 1860 by M. Davaine, and this demonstration was made by the application of the method of culture which M. Pasteur employed in 1857, and which enables him to obtain microscopic organisms in a state of purity—the only means of arriving at certain results. An infinitely small drop of the blood from a case of malignant pustule is taken, and it is sown in the cultivating fluid constituted by a froth of beer-yeast; a little drop of this fluid is taken again, and sown in a new medium of the same kind, and so on. Thus the media of culture may be multiplied indefinitely to a certain extent during years by the aid of a single droplet of blood taken originally from the case, and one may have always a liquid the inoculation of which in certain animals, such as the sheep or Guinea-pig, reproduces in those animals malignant pustulæ. If this fluid is filtered through a plaster filter, nothing results from the inoculation of the fluid parts which have traversed the filter, but, if the figurate elements which remain on the filter be inoculated, all conditions of the pustular disease are produced. It is the same with the cholera of fowls, and perhaps with puerperal septicaemia."

 

Marey on Electrical Fishes.—Of a communication from Professor Marey to the Paris Academy of Sciences on electrical fishes, a brief summary is given in the "Revue Scientifique," from which we learn that the author employed a telephone in studying the nature of the electrical discharge of the gymnotus, and the torpedo. Physiologists long ago pointed out certain analogies of innervation, chemical composition, and structure observable between muscles and the electrical apparatus of these animals. It remained to be discovered whether these analogies also exist in the functionment of the two organs. Marey's experiments go to show that the electrical and the muscular functions are in reality homologous, and that they are destined to explain each other. The author also investigated the question whether in those species of fishes which give the electrical discharge there is to be observed a multiplicity of electrical discharges just as a multiplicity of shocks are to be observed in muscular action. The experiments yielded affirmative results. They were made according to the graphic method, as also with the aid of the telephone, the latter instrument being specially adapted for this kind of investigation, inasmuch as it gives a sound when it is traversed by successive currents of sufficient frequency.

 

Variable Stars.—In directing attention to a certain remarkable star, the "Academy" relates an interesting passage of history connected with it. A Jesuit Professor at Ingolstadt, Christopher Scheiner, was one of the first observers of sun-spots, having noticed them in March, 1611. In accordance with the rule of his order, he communicated his discovery to Budæus, his superior, who, being a disciple of Aristotle, would not accept the observation as correct, inasmuch as no such thing was to be found mentioned in the works of "the Philosopher." When Scheiner had satisfied himself that he had made a true observation, he was permitted to publish the fact, but anonymously. Accordingly, he addressed several letters to Welser, a wealthy Augsburg patrician, and a great patron of learned men; these were printed, and copies sent to Galilei and other astronomers. In the autumn of 1612 Welser published three more letters by Scheiner, under the title "De Maculis solaribus," etc., the second of which, dated April 14, 1612, records observations of Jupiter and his satellites from March 29th to April 8th, among them some observations to which Professor Winnecke, of Strasburg, has lately drawn attention. In order to understand why observations of the satellites of Jupiter were mixed up with those of sun-spots, one must bear in mind that at that time Scheiner still assumed the spots to be merely satellites of the sun, and thus avoided inconvenient questions respecting the purity of the sun's light, which the Aristotelians would not give up. While observing Jupiter's satellites he saw something which offered, as he fancied, a new analogy in support of his opinion; for on March 30, 1612, he remarked in the field of the telescope, besides the four satellites, a fifth star, which he had not noted the previous night. This star decreased in, brightness from night to night, and had, on April 9th, already passed the limit of visibility. Scheiner, moreover, thought he had remarked a small amount of motion, and he accordingly considered the star to be a fifth satellite of Jupiter. The statements contained in his letter agree sufficiently with the assumption that the star was or is a variable fixed star, and the diagrams and descriptions indicate that the conjunction of Jupiter and of the star occurred on April 7th. By means of the geocentric place of Jupiter computed for the date, Winnecke has been enabled to identify the observed star with Lalande's 18,886, a star of the eighth or the seventh to eighth magnitude, which, during the last half century, seems to have varied little in brightness. Variable stars, in the sense of the term as now used, were unknown in Schemer's time, and his description of the rapid decrease of the star's light carries with it some proof of its truthfulness. The spectroscopic observation of this star, with sufficiently powerful instruments, would be very desirable. Its place for 1855, date of the Bonner Durchmusterung, is right ascension 91h. 29m. 21·2s., and declination +15° 52·1'.

 

Identity of Heat and Light.—In a recent lecture, Mr. W. H. Preece, the English electrician, made the following interesting remarks on heat and light: "These two," he said, "are identical in character, though different in degree; and whenever solid matter has imparted to it motion of a very high intensity—in other words, when solid matter is raised to a very high temperature—it becomes luminous. The amount of light is dependent on the height of this temperature; and it is a very remarkable fact that all solid bodies become self-luminous at the same temperature. This was determined by Daniell to be 980°, by Wedgwood 947°, by Draper 977°; so that we may approximately assume the temperature at which bodies begin to show a dull light to be 1,000°. The intensity of light, however, increases in a greater ratio than the temperature. For instance, platinum at 2,600° emits 40 times more light than at 1,900°. Bodies when raised to incandescence pass through all stages of the spectrum; as the temperature increases, so does the refrangibility of the rays of light. Thus, where a body is at a temperature of 250°, it may be called warm; at 500°, hot. At 1,000°, we have the red rays; at 1,200°, the orange rays; at 1,300°, the yellow rays; at 1,500°, the blue rays; at 1,700°, the indigo rays; and at 2,000°, the violet rays. So that any body raised to a temperature above 2,000° will emit all the rays of the sun. Inversely, the spectroscope may thus be enabled to tell us the temperature of the different lights, and it is perhaps because some lights do not exceed 1,300° that we have all the rays beyond the yellow."

 

A Horse with a Load in his Stomach.—Dr. Albin Kohn recites in "Die Natur" the particulars of the sudden death of a horse, caused by the presence of a stony concretion in the animal's stomach. The horse was to all appearance perfectly sound and well one morning when carrying his master about his estate, when suddenly he fell dead. A veterinarian opened the carcass to ascertain the cause, and found in the abdominal cavity a stone of about eight pounds' weight, and in the wall of the stomach a hole of corresponding size. The stone was submitted to Dr. Peters, of Posen, for analysis, who first cut it into halves. Each half of the rather round stone—called by Dr. Peters "magenstein," i. e., stomach-stone—looked very much like a Chester cheese. The diameter of the cut surface was from 15 to 1712 centimetres, and concentric rings are visible in it. At the center its texture is radiate. Dr. Peters supposes the animal at some time swallowed a fragment of millstone, and that around this nucleus numerous layers were afterward deposited. Externally the stone is smooth, rather hard, and of a grayish-yellow color; its composition is: ammoniomagnesic phosphate 8712 per cent., organic matter 614, water 113, silicic acid 113; other salts 23 per cent.

 

"Jumping Frenchmen."—It is a very instructive narrative which Dr. G. M. Beard publishes of the doings of the "Jumpers" of the woods of Maine and Canada. These jumpers are mostly half-breed French-Canadian lumberers who have acquired the permanent habit, which they can not control, of jumping or striking out with their hands, when commanded to do so by any one who chances to lie near. The habit appears to have been acquired, in the first instance, by tickling one another in the winter camps where they cut lumber. The men are extremely ignorant, and one of their pastimes is this practice of tickling one another. When the jumpers are excited to strike or jump, or to perform any of their automatic acts, they present the appearance of entranced persons: their faces pale, eyes fixed and glassy, and limbs trembling. One of these jumpers is a waiter, and when told suddenly to "drop it," he at once lets fall whatever he may have in his hand. Another has so susceptible a stomach that he at once throws up his meal when anyone "gags" or makes the motion of vomiting in his presence. The man has grown thin, and at one time was almost starved. One man, standing on the bank of a pond with a five-dollar gold piece in his hand, was told to "throw it," and threw the money into the water. Another was standing near a kettle of fish; being told to "jump," he leaped into the kettle. In these acts the jumpers are absolute automatons, utterly without volition or responsibility: they are to be compared to persons afflicted with St. Vitus's dance, hysteria, or epilepsy. Performances of a somewhat similar character were, last winter, witnessed in a town of Vermont during a revival of religion. Here the victims of abnormal religious excitement would roll on the floor in most absurd and undignified attitudes, whence the appellation of "the holy rollers!"

 

New Process for the Protection of Iron Surfaces.—A new process for protecting iron from rust has been invented by M. Dodé. It consists in coating, either by means of a bath or a brush, any objects in cast or wrought iron (freed from the damp they may contain) with a composition of borate of lead, oxide of copper, and spirits of turpentine. This application soon dries on the surface of the iron, and the objects are then passed through a furnace, which is heated from 500° to 700° Fahr., according to the thickness of the articles under treatment, so as to bring them-to a cherry-red heat when passing through the center of the furnace. At this point the fusion of the metallic pigment takes place; it enters the pores of the iron, and becomes homogeneously adherent thereto, covering the objects with a dark coating, which is not liable to change under the action of the air, gases, alkaline or other vapors, nor to scale off from the surfaces to which it has been applied. When any considerable depth of "inoxidation" is desired, the object may be immersed in the composition for the time requisite to absorb a sufficient quantity of it. This process supersedes painting and varnishing, and iron objects thus heated are impervious to rust. The cost of application is about half a cent per superficial square foot.

 

The Mance Heliograph.—The Mance heliograph, an instrument for signaling by means of reflected solar rays, is now in use among the British forces in South Africa. The signals made by the Mance heliograph are visible, under favorable conditions of position and atmosphere, to very great distances, and have been read as far as eighty and a hundred miles. It consists of a specially prepared mirror, with mechanism for reflecting the sun's rays with absolute precision to any required spot, notwithstanding the sun's apparent motion. By pressure en a finger-key the flashes are made of short or long duration, thus adapting the instrument to the Morse code of telegraphy. A second mirror is provided to permit of signaling being carried on irrespective of the sun's position. The instrument intended for field service weighs from six to eight pounds, and is mounted on a light tripod stand. The working parts are protected from injury during transit, and the complete apparatus admits of being easily carried, as it is also efficiently worked, by one man.

 

Experiments in Opium-Smoking.—The Russian traveler, Dr. Miclucho Maclay, while recently on a visit to Hong-Kong, experimented on the effects upon himself of smoking opium. The experiment was made at the Chinese Club, and was under the direction of Dr. Clouth, who made the following notes: Mr. Maclay was in normal health, and had fasted eighteen hours before commencing the experiment. He had never smoked tobacco. Twenty-seven pipes, equivalent to 107 grains of the opium used by the Chinese, were smoked in two and three quarter hours at tolerably regular intervals. The third removed the feeling of languor caused by his long fast, and his pulse rose from 72 to 80. The fourth and fifth caused slight heaviness and desire for sleep, but there was no hesitation in giving correct replies to questions, though he could not guide himself about the room. After the seventh pipe the pulse fell to 70. The twelfth pipe was followed by singing in the ears, and after the thirteenth he laughed heartily, though without any cause that he can remember. Questions asked at this time were answered only after a pause, and not always correctly. He had for some time ceased to be conscious of his actions. After the twenty-fifth pipe, questions asked in a loud tone were not answered. After the last pipe had been smoked, he remarked, "I do not hear well." Forty minutes later there was a slight return of conciousness, and he said: "I am quite bewildered. May I smoke some more? Is the man with the pipe gone already?" Fifteen minutes later he was able to go home, and then retired to bed. He woke the next morning at 3 a. m. and took a hearty meal, after his fast of thirty-three hours. During the next day he felt as if he had bees in a great hollow in his head, as well as a slight headache. The organs of locomotion were first affected, next came sight and hearing, but Mr. Maclay is positive that there were no dreams, hallucinations, or visions of any sort whatever.

 

Descartes on the Invention of the Telescope.—Concerning the invention of the telescope, Descartes, in 1637, wrote as follows: "This invention, as illustrious as it is useful, is, to the shame of our science, due to chance and mere experiment. About thirty years ago there lived in Alkmaer, in Holland, a certain Jacob Metius, who had never studied, though both his father and his brother were professors of mathematics. He found his greatest pleasure in making burning-glasses and mirrors; and when he was thus once in possession of a lot of glasses of different forms he happened to look at the same time through two glasses, of which the one was a little thicker in the middle than on the edge, and the other thinner in the middle. He afterward fixed them in a tube, and in-that way originated a telescope, from which all the later ones have been made, for as far as I know nobody as yet has sufficiently explained what form these glasses by right ought to have. On the 17th of October, 1608, this Jacob Metius (otherwise Adriaanz) applied to the States-General of the Netherlands for a reward as the inventor of the instrument two years previously. But one of his own countrymen had anticipated him in this application, for Jan Lapprey (otherwise Hans Lippersheim) had some days before presented to the States a similar instrument. Thus, then, the first authentic publication on record of this great invention was made when Lapprey delivered his telescope to the States-General."

"This Jan Lapprey," says the author of a paper in "The Observatory," "was born in Wesel, and followed the trade of a spectacle-maker in Middelburg. On October 2, 1608, he solicited the States for a patent for thirty years, or an annual pension for life, for the instrument he had invented, promising them to construct such instruments only for the Government. After inviting the inventor to improve the instrument, and alter it so that they could look through it with both eyes at the same time, the States determined, on October 4th, that from every province one deputy should be chosen to try the apparatus and make terms with him concerning the price. The committee declared, on October 6th, that it found the invention useful for the country, and nine hundred florins were offered to Lapprey for the instrument. He had at first asked three thousand florins for three instruments of rock-crystal. He was then ordered to deliver the instruments within a certain time and the patent was promised him on condition that he kept the invention a secret. Lapprey delivered the instrument in due time. He had arranged it for both eyes, and it was found satisfactory."

 

A Carnivorous Goose.—In communicating to "Nature" an account of a goose which had learned to eat flesh, the Duke of Argyll remarks upon the circumstance as being extremely curious, but at the same time notes the fact that cows are largely fed on fish-offal in Scandinavia. This carnivorous goose is in the possession of Mr. W. Pike, of the island of Achill, Ireland, and was hatched in 1877 by a tame eagle. The eagle having laid three eggs, Mr. Pike took them away, substituting for them two goose-eggs, upon which the eagle sat, and in due time hatched two goslings. One of these died, and was torn up by the eagle to feed the survivor, who, to the great surprise of its foster-parent, refused to touch it or any other flesh-meat offered by the eagle. In course of time, however, the goose learned to eat flesh, and now the eagle always calls it by a sharp bark whenever there is any fresh meat in the cage. On hearing the call the goose hastens to the cage, and greedily swallows all the flesh and offal which the eagle gives it.

 

The King-Vulture.—A traveler in Colombia, André, confirms from personal observation the popular belief in that country that the urubu (or black vulture) dreads the king-vulture (Sarcoramphus papa), and slinks away when that monarch of the Cordilleras makes his appearance. On one occasion André saw the carcass of a cow covered with urubus which were greedily devouring it. Suddenly a black point appeared in the sky overhead. One of the urubus uttered a cry, and at once all the heads were raised to observe the enemy, who was coming ever nearer and nearer. In less than a minute the urubus had fled to a respectful distance, and the king, descending like a thunderbolt into the entrails of the carcass, began his meal with avidity. This operation took up half an hour, the urubus in the mean time standing around in a wide circle. They did not return to the carcass till after the king had risen majestically into the upper air.

 

The Size of Lightning-Rods.—In calculating the relative sectional areas of copper and iron lightning-rods, certain important factors are commonly overlooked, and thus of necessity incorrect results are obtained. The relation usually given, that an iron rod should have four times the sectional area of the copper rod, is based on the fact that copper conducts electricity six times as well as iron, while the melting-point of iron is about fifty per cent, higher than that of copper, and 6 divided by 15 is equal to 4. This simple treatment, as is pointed out by R. S. Brough, in the "Philosophical Magazine," is incomplete, because it neglects these factors: 1. The influence of the rise of temperature in increasing the electrical resistance of the metal; 2. The difference between the specific heats of the copper and iron; 3. The fact that the iron rod being made several times more massive than the copper one, it will require a proportionally greater quantity of heat to increase its temperature. Taking these considerations into account, Mr. Brough finds that the sectional area of an iron rod should be to the sectional area of a copper rod in the ratio of 8 to 3.