Popular Science Monthly/Volume 18/December 1880/Popular Miscellany

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Popular Science Monthly Volume 18 December 1880  (1880) 
Popular Miscellany
 

POPULAR MISCELLANY.

Lieutenant Schwatka's Arctic Journey.—The gap left in our knowledge of the ill-fated Arctic Expedition of Sir John Franklin, by the successive search-parties sent in quest of the explorers, has now been filled, as completely as it seems ever likely to be, by the remarkable achievement of Lieutenant Schwatka and his comrades, who have recently returned from their Arctic journey, after an absence of more than two years, Though the expedition was the poorest equipped of any of the similar ones which preceded it, it has accomplished more than any other, and that in the face of what would have seemed to less intrepid explorers insurmountable difficulties. The expedition of Sir John Franklin, consisting of the two ships Erebus and Terror, with a total party of one hundred and twenty-eight men, was sent out in the spring of 1845, and was never more seen. The mystery which enshrouded their fate was first unveiled by Dr. Rae, who, in 1853, found and brought to England a number of relics of the missing party, which are now in the British Museum, Dr. Rae's journey was made in the same general direction as that of Lieutenant Schwatka, but not over the same ground. Another expedition was sent out in 1858 under the command of Sir Leopold McClintock, who succeeded in obtaining the only written record that has been found. This showed that Franklin died on board ship in 1847, and the task of leading the way over the trackless Arctic fields, where the whole party perished miserably from cold and hunger, devolved upon Captain Crozier, the next in command. Franklin penetrated as far north OS latitude 77°, going through Baffin Bay, Barrow Strait, and up Wellington Channel, but was forced to return southward, and in latitude 70° was frozen in by the ice toward the close of 1846. The vessels were abandoned in the spring of 1848, and the party, now consisting of one hundred and five men, betook themselves to the land in the hope of reaching some outpost of the Hudson Bay Company. They reached an island named King William Land, beyond which they never got. The subsequent expeditions of Dr. Kane and Captain Hall gleaned some further information, but there was still much to be learned of the way and place in which the party perished, and of what had become of the records which they must have had with them. It was to clear up these points that the Schwatka expedition undertook its perilous and fortunately successful journey, upon information regarding the existence of records which seemed reliable. This information was that one Captain Barry, of a whaler, while wintering in Repulse Bay, had been given a spoon by the Esquimaux, which had belonged to the Franklin party, and that this captain had subsequently overheard some natives talking, and learned that this spoon came from a cairn in King William Land where there were others, as well as books and papers. When the expedition arrived at its destination at a northern point of Hudson Bay, this story was found to be without foundation. Lieutenant Schwatka, however, determined to make the trip to King William Land, in the hope of obtaining new information of value. The journey was in every way a formidable undertaking, having to be made on sledges, many hundred miles across a totally unknown country, which had to be depended upon for food. The party consisted of four white men and thirteen Esquimaux, provided with but one month's provisions, but also amply supplied with the best and most accurate American guns, to whose perfection, as it proved, they were indebted for being able to successfully accomplish the task. The party left their camp upon Hudson Bay, which they had named Camp Daly, on the 1st of April, 1879, and reached it again in March, after eleven months' absence, having traveled more than three thousand miles, and experienced a degree of cold that seems incredible. The lowest temperature was —71º, or 103º below the freezing-point, while the mean temperatures for the months of November and December, 1879, and January, 1880, were —49º, —50º and —53·2º. In such temperatures as these any object sears the skin as a red-hot iron, the slightest wind burns the face, and meat, hot from a boiling pot, freezes before it can be eaten. The story of the wanderings of the Franklin explorers, as learned by this party from the natives, and as confirmed by their personal search, is terrible in the extreme. These men were but a few hundred miles from waters frequented by whalers, and yet they all perished, and perished seas to leave hardly any evidence of their journey. So far as it could be traced, it was by Lieutenant Schwatka's party, and the bones that were found at different points along the desolate shore of King William Land were buried. Only one skeleton could be identified—that of Lieutenant Irving, and this was brought away by them. It was known by means of a medal found near by, which the natives, in their desecration of his grave, had forgotten to take. It was learned from the natives that one of the ships was sunk at a point about five miles west of Grant Point, near the Adelaide Peninsula. As the Esquimaux did not know how to get in by the deck, they cut a hole in the side on a level with the ice, through which they carried off what provisions and other things they could find, and in the spring, when the ice broke up, the ship sank. Across this Adelaide Peninsula, at a point named Starvation Cove, evidences were found that it was here that the last remnant of the party perished, and with them the records, Lieutenant Schwatka believing that they are irrecoverably lost. All the relics found here by the natives, as well as at other points, were destroyed, having been given to the children to play with, and in time were broken up and lost. Besides the knowledge gained of the Franklin party, the searchers obtained geographical results of value, and found a considerable error in the Admiralty chart, in the mapping of Back's River, which they found to extend a good deal east of south, instead of west of it.

 

The Marshall-Islanders.—A work recently published by Franz Hemshein, a resident German merchant and consul, on the language of the Marshall Islands, affords some interesting facts concerning this little Polynesian group and its people. The islands are of coral, and are called atolls, having for their foundation a ring-shaped coral reef on which a land surface has been formed of varying length, but only a few hundred yards in breadth, and rising but a few feet above the water-line. Channels through these banks connect the inclosed lagoons, which are seldom more than thirty or thirty-five fathoms deep, with the outer water. The channels are entirely wanting or are too shallow for ships in some of the islands. The thin soil supports a scanty vegetation, which is limited to only a few of the species peculiar to the South-Sea regions; but many useful plants have been imported from other islands and do well. The fauna is likewise insignificant, but has been increased by importations from abroad, along with which the universal rat has been introduced. The inhabitants are a small, slightly built people, who age early; the women have rounder faces than the men, with thin, fleshless hands, and begin to fade before they reach maturity. Four ranks arc recognized among them. The lowest are the Armidwon, or Kajur, who own nothing; above them arc the Leadagedag, to whom they must bring provision, and whom they must obey. Men of the latter class are permitted to own property. The third rank, called the Budag, is composed of the brothers and sous of the king. Over all is the Irod, or king, from whom the Leadagedag receive their commands. The Kajurs are allowed to have but one wife; men of the other classes may have more. The Kajur has the right to take the single wife from a man of lower condition than himself, but the men of the second rank are not permitted to speak with the wife of the king; and if the king goes abroad, leaving his wife at home, all the Leadagedag and the Budag, except the sons of the king, must leave the island. If a woman in the higher ranks is put away by her husband, as may happen if she is childless, she can not be taken in marriage by any one of a lower condition; but a man may marry a woman of a higher rank than his own and be raised to her rank. The food of the islanders is scanty. Young cocoanuts take the place of the drinking water, which is brackish. Cocoa-nuts, pandanus, and bread-fruit form the regular food. Arrow, root, brought from the northern islands, cooked with finely cut cocoa-nut, forms a favorite dish. A kind of conserve is made by roasting the pandanus-fruit over a bed of hot coals and covered with hot sand. In two days the fruit is taken out, sliced, dried in the sun, and pressed into rolls, which can be kept for two years. Another preparation, piru, is made from the bread-fruit. The fruit is cut up, steeped in salt water, and beaten; it is then put away in a shady place and covered with leaves; the soft mass is kneaded on the second day, laid away for a week, and kneaded again, when it is ready for use, and will keep good for five or six months. The principal disease from which the people suffer, and the most fatal one, is a catarrhal cold resembling the glanders in beasts. Europeans are also liable to take it, but they have it in a milder form, and do not die of it. A skin-disease called the gogo is generally prevalent, but is not commonly dangerous. This disease is not due to lack of personal cleanliness, for the natives are so much in the water as to make such a condition rare, and it prevails chiefly with the men, who are most in the water. The guild of the heathen priests consisted chiefly of diviners. God was supposed to appear to them and disclose the future to them. During the interview, which usually lasted for two or three days, they took no food. They never ate or drank out of dishes that had been used, and broke the cups after they had drunken from them. They were supposed to know about the wind and the weather, and the chances of success in enterprises, and were called into the sick and expected to foretell whether they would live or die. Remedies for disease were and are wholly unknown. Warm water, a few leaves, and especially rubbing, which is carefully attended to by the women with conjuring words, are the only medicaments. The friends of the sick man were formerly accustomed to come to him, bringing pandanus leaves, which they would fold together in patterns of equal size; if the last fold came out of the same length with the others, the omen was considered a good one for an impending recovery; if otherwise, the sick man was taker away to a distance, depending on the length of the last fold. These and many other customs have gone or are going out of use, and occur only exceptionally in places where one tenth of the population have been converted to Christianity. Fights are rare; wars are carried on chiefly by one party trying to destroy the cocoa palms or burn the houses of the other. They never come to a battle, but are conducted by siege, and generally end by the besieged party yielding. The worst damage ensues after the war, when, the trees being cut down and the land wasted, a famine of five or six months' duration is nearly certain. The principal occupation of the inhabitants is fishing. To catch the flying-fish a large torch is burned in a dark night upon a fast sailing canoe. The fish fly toward the glimmer and either strike the sail and fall down or are caught by the skillful fisherman with a long-handled net. The yellow-tail fish swims in schools, and is caught with two canoes which, tied together, draw a cord after them on the top of the water, and drive the fish into shallow places, where they are caught with little trouble. It is a curious fact that the fish will occasionally leap over the cord, but will never swim away under it. Mats and hats are artfully woven out of the bark of a shrub called the loa, and colored in handsome patterns of yellow, red, and black. The natives formerly made numerous voyages to the islands of the whole Marshall group, and had charts of them, which were drawn and copied on sticks and stones.

 

Improvements in Electro-Motors and Dynamo-Machines.—In a paper recently read before the British Association, Mr. T. Weisendanger takes exception to some of the received theories regarding electro-motors and dynamo-generators, and points out an improved mode of construction for both. In regard to the relations of these two classes of machines, it has generally been held that the most efficient generator is also the most efficient motor. This Mr. Weisendanger considers erroneous. Dynamo-generators are efficient only when their field-magnets are able to retain at all times a certain amount of residual magnetism. Their cores are, therefore, usually made of hard cast iron, or, if of soft iron, they are attached to masses of cast iron so that these form part of them. None of the efforts hitherto made to construct dynamo machines with soft-iron cores have met with success, and, as electro-motors to give the best results should have such cores, machines can not be made that will give the maximum efficiency in both kinds of work. The fact that the attempts to make dynamo machines with soft-iron cores have resulted in failure, he considers, proves that the current theory of their action, viz., that the electricity is generated by the inductive action and reaction between the field-magnets and the armature, is inadequate. Even wrought iron contains some residual magnetism, and in large masses, and after it has been subjected to strong magnetization, the amount is considerable. By the theory, the smallest amount of such magnetism would be sufficient to start the action of the machine. Experiment, however, shows that this is not the case. Mr. Weisendanger does not offer a new theory, but insists that the present one needs to be amended to correctly express the facts. Attention is also called to the idea underlying the work of some recent experimenters, that the power of an electro-motor can be indefinitely increased by augmenting that of the field-magnets. This is characterized as a mischievous theory whose outcome is perpetual motion. The author, on the contrary, holds that there is a definite relation between the power of the field-magnets and the armature, which has yet to be experimentally determined. Assuming the relation of these sets of magnets to be one of equality, he has constructed a motor, in which the cores of the field-magnets are light pieces of soft iron, that gives very satisfactory results. Further experiments to determine the exact ratio of the power of the field and armature, he believes, will result in a much more perfect machine. The most novel and perhaps important part of Sir. Weisendanger's paper is that relating to the proper method of revolving the armature before the poles of the field magnets. The present practice is to make the cores of the field-magnets and those of the armature of such shape that the circles in whose circumference they lie are concentric. The defect of this arrangement is, that the armatures approach the magnets through the space in which the intensity of the field is at a minimum. After the armature reaches the magnet, the distance between the two remains constant while they are passing each other. Mr. Weisendanger holds that in generators the strongest currents will be induced, and in motors the greatest amount of power obtained when the armature not only revolves in the most highly concentrated field, but when its entire motion is either one of approach to or withdrawal from the field-magnets. He, therefore, proposes that the field-magnets be set at an angle to the circle described by the revolving armature. This latter then approaches the former continuously to the very instant of its leaving them. The greater the number of magnets the more powerful the action, as the armature is throughout its entire movement either approaching or receding from the field-magnets. Mr. Weisendanger is very hopeful of the future possibilities of electricity. Our present machines he believes to be but very imperfect appliances, which further research may so improve that the electric current will eventually perform all the services now rendered by combustion. He looks not only to electricity to furnish light, and, through the medium of present unutilized natural resources, motive power, but heat as well. The exhaustion of fuel-supply will inevitably drive us to seek and find some other agency to do our work, and this, he thinks there is good reason to believe, will be found in electrical energy.

 

A New Smelting-Furnace.—The utilization of petroleum for fuel in the various metallurgical operations, in steam generating, and generally where coal is industrially used, has been a favorite project with inventors for a dozen years or more. The advantages of such a fuel are very great, and the reward to the successful inventor of an apparatus that would make its use practicable would be correspondingly large. Like gas, a liquid fuel is under perfect control, and is in a form allowing of perfect combustion if properly burned. The fuel is, moreover, very abundant, the production having been for some time past in considerable excess of the demand. In one district alone something like six thousand barrels are daily running to waste through lack of storage capacity, and one of the largest producers of oil is now obtaining from the wells about fifteen thousand barrels per day more than can be marketed. The oil companies, as well as inventors who have hoped to make a fortune by a successful furnace, have been unceasing in their efforts to turn this fuel to industrial uses, but so far the devices—and they have been many—have uniformly failed. A furnace is, however, now being developed which seems to promise, if not a complete solution, at least a partial solution of the problem. The furnace consists, in reality, in an immense blowpipe-flame, which is made to play upon the ore to be smelted, when used for metallurgical purposes, and to pass through boiler tubes when used for steam generating. In the metallurgical apparatus there is first a fuel-furnace in which any ordinary fuel may be used, or oil if preferred. Against the upper portion of the flame from this furnace a blast of air is projected, similar to that from the mouth blowpipe against the flame of a spirit-lamp. Into this blast, at the point where it strikes the fuel-furnace flame, a stream of oil is introduced. The on-going blast and the heat of the flame vaporize the oil, which is then in a condition to be completely consumed. The result of this arrangement is the production of a column of flame, some thirty or forty feet long, of high temperature. This flame is projected horizontally through an iron cylindrical shell, lined with tire-brick with a facing of graphite, into which the ore to be reduced is fed from a hopper at the farther end. The shell is slowly rotated, so that the entering ore, tumbling about, is brought into intimate contact with the flame. It is also slightly inclined, that the material may slowly feed into the flame, and the melted material run down into the crucible at the lower end, where it is tapped and the slag run off in the usual way. The farther end of the revolving cylinder is let into a chamber, built of brick, stone, or clay, which is divided into compartments by walls or sheets of incombustible material kept constantly wet by running water. The hot gases, carrying vapors of the metals and other ingredients of the ore, are here gradually cooled down and condensed, the character of the condensation depending upon the materials present in the ore. The burned gases are withdrawn from the condensing chamber by means of an exhaust-fan, and discharged into the atmosphere. The air and oil are both under perfect control, so that a heat suitable for smelting or for vaporizing can be produced at will. Several furnaces are shortly to be put into operation for the reduction of ores of the precious metals, on which experiments have so far chiefly been made. The inventor, however, expects to be able to use it successfully in making iron and steel, as well as in burning lime. A modified form is also suitable to the burning of pottery and glass-making. In using it for generating steam, the boiler flue is made large, the flame at no point coming in contact with the metal, thus avoiding the burning out of the boiler, the chief difficulty encountered by most of the other devices using oil-fuel for steam-making. The experiments with the furnace upon an industrial scale have been as yet too few and imperfect to thoroughly test its value, but they seem to warrant the opinion that the furnace has capabilities that promise very well for its future usefulness.

 

The Markings of Meteoric Stones.—M. Daubrée, the eminent French geologist, in his recently published work on "Synthetic Studies in Experimental Geology," describes some experiments that he has made for the purpose of ascertaining the cause of the peculiar appearance of the surface of meteoric stones. These bodies are covered with a blackish coating, which is sometimes dull and sometimes brilliant, and indicates unmistakably that they have suffered modifications in passing through the atmosphere. Their fracture presents a globular surface, similar to the structure of terrestrial rocks, showing that a strong cohesion has been produced at the moment of their formation. The outer surface is also covered with rounded depressions forming little capsules. M. Daubrée had remarked that when a cannon loaded with coarse-grained powder was fired off, some grains, which were only partly burned, would fall at the muzzle of the piece. The hollowed surface of these grains bore a striking resemblance to the forms seen on the meteorites. He then performed an experiment by taking a rectangular plate of steel, rolling it up in such a way that it should be fully enveloped by the gases from the powder, putting it in a closed steel chamber, with a quantity of powder, and firing off the powder by means of the electric spark. The duration of the deflagration was less than half a second. The gases acquired a tension of from one to two thousand atmospheres, and a temperature estimated at about 3,600º. The action, though of very short duration, gave surprising results. The surface of the plate was hollowed into irregular furrows, which demonstrated the force of the gaseous currents, and a powder of sulphuret of iron was found in the bottom of the vessel. A half a second, then, was all the time that was required to produce a partial fusion of the steel, a considerable blowing up by the gases, and such a chemical action as the formation of a sulphuret of iron. The experiment was repeated with dynamite and other explosives, with identical results. From them, M. Daubrée has deduced the following interpretation of the meteoric phenomena: the meteorites enter the terrestrial atmosphere with an enormous swiftness. The great pressure of air to which they are subjected explains the incandescence which takes place, and the superficial fusion of the mass. The part of a projectile of this kind which is at the moment in front rams the air and compresses it exceedingly, and causes it to be agitated by energetic gyratory movements. In whirling thus, under such pressure, the air tends to screw and hollow out whatever it rubs against, and this mechanical action is accompanied and reënforced by a chemical action due to the combustible nature of the meteoric rocks at these high temperatures. These rocks contain enough particles of iron in the native state, or as a sulphuret, to largely favor combustion and disaggregation. Under these circumstances, the hollows are produced, which appear on one side or on all sides of the projectile, accordingly as it has not or has a motion of rotation. M. Daubrée has given to these hollows the name of piezoglyptes.

 

Relation of Age and Marriage to Suicide.—It has been a mooted question whether the old or the young were more prone to suicide. Statistics published by Dr. Bertillon, in an article on marriage in the French "Encyclopædic Dictionary of the Medical Sciences," prove that the propensity increases with advancing age. They are reënforced by statistics recently published in Sweden, which lead to substantially the same conclusion. The proportion of the number of suicides of the more advanced ages to the whole number of persons of corresponding ages appears to be less in Sweden than in France, but aside from this the proportion increases regularly in both countries from the age of fifteen or twenty years to that of sixty years. After about sixty years the tendency in both countries appears to diminish. The proportion of suicides among women is less at all ages than among men, but increases with the advance of years as with the men. The statistical work of Signor Morrelli, recently published at Milan, lends additional support to these views. Dr. Bertillon has also collected facts bearing on the effect of marriage upon the tendency to suicide, from which he has deduced the principles: 1. That widowers and widows commit suicide more frequently than married persons; and, 2, that the presence of children in the family makes the probability of suicide more remote. The salutary influence of children is equally marked with married and widowed persons, with men and women. The Swedish statistics may be brought in again to enlarge our knowledge on this point by showing the combined influence of marriage and age. According to these tables, the difference in the liability of married men and celibates, while they are still young, is very slight. The tendency to suicide then increases slowly among married men as they grow older, and at its maximum (at about sixty to sixty-five years of age) is two and one half times (26 in 100,000) what it was at the adult age (10 to 11 per 100,000). After the sixty-fifth year it diminishes. With unmarried persons, on the other hand, the tendency increases with almost a geometrical progression. At twenty-five years of age it is more than double (26 per 100,000) what it is with married persons of the same age (11 per 100,000), and at seventy years is eleven times as great (230 against 21 per 100,000); and after this period it goes on increasing as fast as ever, while the proportion for married persons is diminishing. The phenomena with women are analogous, but less marked. It is found, by comparing the statistics of the two classes, that the general increase in the tendency to commit suicide with advancing age can be almost wholly accounted for by this progression of suicides among the unmarried. The difference in the liability of the two classes may be partly explained by setting off the regularity of habit which married life and particularly the care for children induce with the irregularities to which the unmarried surrender themselves, of which the most damaging is drunkenness. Signor Morrelli says that drunkenness causes thirty-one per cent, of the suicides in Denmark, and that a similar rule prevails everywhere.

 

Artificial Lights.—The great point of difference between natural and artificial lights. says Dr. Javal, the French occulist, is the excessive feebleness of the latter. A lamp or a gas-jet makes an insignificant impression in daylight. The light of a million candles burning in a room would be vastly inferior in intensity to that of the direct rays of the sun. The pupils of our eyes are considerably larger in the most brilliantly lighted room than they are in daylight. We seek the brightest places of resort at night, and use the strongest lights we can afford in our homes, employing every means to make them stronger. Persons with imperfect sight are fatigued in working with artificial lights because the enlargement of their pupils gives full play to faults which are mitigated under the contraction of the aperture which a strong light induces. The spectra of all artificial lights, except the magnesium and electrical lights, are different from the spectrum of sunlight in that they are dark on the most refracted side, that of the blue, violet, and chemical rays. It may be that this quality compensates in part for the greater dilatation of the pupil which these lights require by reducing the amount of chromatic refraction which would otherwise take place. It does not appear, however, that any workmen prefer such lights to sunlight. It has been suggested that the presence of these rays in the electric light might cause it to be injurious. If that should prove to be the case, any evil effect might be remedied by shading the pencils with yellow-tinted globes. No complaint has been made, however, of bad effects arising from the proper use of this light. Those who have studied it most attentively have felt no inconvenience except when they looked intently at it without guarding their eyes. It is not intended to be used thus; and, if we judged by this criterion, the sun would be the worst of all lights. When the electric light was first introduced into the freight depots in Paris, the workmen complained of being dazzled by it. After some weeks, it was taken away, and gas was put in its place, when a general outcry went up against the darkness.

 

A Solar Machine.—The idea of applying the heat of the sun directly as a motive force has been entertained as within the limits of possibility for some time. A Frenchman, M. Mouchot, devised a machine, about two years ago, for concentrating the rays of the sun so that they could be made to perform some slight offices. M. Abel Pifre, an engineer associated with M. Mouchot, has carried on some experiments in Algeria with an adaptation of his machine which have had a promising degree of success. His apparatus was small, yet it was sufficient, by the aid of the sun of last October, to produce steam enough to keep a sewing-machine in continuous motion, cook food, and boil water. M. Mouchot's machine consists of a reflector in the form of a truncated cone, which concentrates the rays of the sun upon a kettle placed in the axis of the cone, with a bell glass to cover the kettle and protect it from external cooling. Such machines are not likely to be of much practical use in temperate climates, where the sun is comparatively weak and often clouded; but in hot, arid regions, like the deserts of Africa, they may possibly yet be employed advantageously.

 

Consumption and Climates.—Dr John C. Thorowgood, of the London Hospital for Diseases of the Chest, in a paper on "Atmospheric and Climatic Influence in the Causation and Cure of Pulmonary Disease," distinguishes between two classes of phthisis, or consumption of the lungs, in which the operation of this influence is very different. The first kind, the consumption which originates in catarrh, cold, or some inflammatory attack, prevails in raw, cold climates, and is relieved by going to a mild climate. The second kind, true tubercular consumption, comes on insidiously, often from no cold caught, from no privation of food, but simply from some inherent, perhaps hereditary vice in the system, and is a febrile disease, having much the character of rapid blood-poisoning. It is not peculiar to cold climates, and is not relieved by sending the patient to a mild one. The worst that can be done in cases of either form of disease is, to confine the patient closely to one room, and let him breathe over and over again the same atmosphere, while the cough is kept checked by opiates. In this way, says Dr. Thorowgood, consumption may be cultivated and developed from the first class into the more serious form of the second class, so that it becomes a fearfully destructive malady. "In the cases of young children who are kept very close in heated rooms, and who are said to be always taking cold, we often see most obstinate cough and catarrh, due to the throwing off from the air-passages of a weak, poorly-nourished epithelium, which in time may choke the air-cells, and so lead to pulmonary consumption. The cure consists in laying aside paregoric and squills while we feed the epithelium with pure air. Appetite soon returns, and the cough speedily takes its flight." The tendency of confinement in a close atmosphere to cause blood-spitting and consumption has been demonstrated by the statistics obtained by Dr. Gray when engaged in investigating the effects of certain trades on the health of those employed. The author of the paper under notice has seen excellent results, in removing lingering inflammation after an acute attack on the chest, follow a sojourn at Torquay, Ventnor, and similar mild, warm health-resorts; but when the disorder has passed from the inflammatory stage to one that involves the general nutrition, and is marked by softening and breaking down of lung-tissue, with night-sweats and copious purulent expectoration, he has never seen any good come of a residence in a mild, sedative climate. On the other hand, he tells of several cases in which persons suffering from the latter form have been relieved, and have even recovered after being sent to a cold, bracing climate, or to a high mountain elevation. The author's views were confirmed, in the discussion by the medical society before which it was read, by several speakers. The president of the society mentioned three cases of complete cure of decided pulmonary consumption of non-catarrhal origin by change of air—in one case to Moscow, in two others to Canada. Another speaker mentioned cases of. catarrhal phthisis that had been cured by sojourn at mild resorts.

 

Effect of Physical Training on Respiration.—M. Marey has made an investigation of the modifications which are induced in the respiratory movements by the fact of muscular action. It is well known that muscular action provokes, in those who are not accustomed to it, panting, that is, a respiration stronger and more frequent than the normal respiration. This is in consequence of the greater rapidity of the current of blood which in its abundance demands, in order to pass through the lungs, more frequent or more ample respirations. The habit of muscular exercise, running, for example, has the effect of gradually adapting the respiratory function to the most rapid circulation which can pass the lungs. The respiratory type acquired by the gymnast consists in an enormous increase in the expansion of the chest and a notable retardation of the thoracic movements. M. Marey and Dr. Hillairet selected five recruits and registered the rate of respiration of each of them when at rest, and again after they had run a course of six hundred metres at the gymnastic pace. By following the changes of respiration of these gymnasts from month to month, a series of curves was obtained, and the following results were furnished: At first, respiration was very perceptibly modified by the running; but toward the end of the experiments, that is, after four or five months of the exercises, it was almost impossible to distinguish any change in the respiration of the men who had run; and this, notwithstanding their gait had became a little more rapid, and they ran over the six hundred metres in three minutes and fifty seconds. The figures show that the modification of the respiratory movements is permanent—that is, that it is maintained when the man is at rest. The number of respirations is reduced, in the mean, from twenty to about twelve in a minute, and their amplitude is more than quadrupled. We may conclude, then, that these soldiers, after having experienced the effects of gymnastic training, breathe about twice as much air as before they were subjected to the discipline.

 

Expectant Attention in Animals.—A remarkable instance of sagacity in animals is described in an article on "Mental Physiology" in a late number of the "Edinburgh Review," in the case of a dog that belonged to Professor Huggins. This dog, Kepler, had the faculty of answering correctly with his barkings arithmetical questions, including such problems as giving the square root of nine or sixteen, or the result of adding seven to eight, dividing the sum by three, and multiplying the quotient by two. No power of calculation was implied in this exercise, or operation of the understanding, however it may have seemed. The case was simply one of what is called by physiologists expectant attention. A clew to the process is given by the statement in the story that, until the solution was arrived at, Kepler never moved his eye from his master's face, but the instant the last bark was given he transferred his attention to the cake which was always held before him as a reward for a successful performance. Professor Huggins, the writer continues, was perfectly unconscious of suggesting the proper answer to the dog, but it is beyond all question that he did so. The wonderful fact is, that Kepler had acquired the habit of reading in his master's eye or countenance some indication that was not known to Professor Huggins himself. Professor Huggins was engaged in working out mentally the various stages of his arithmetical processes as he propounded the numbers to Kepler, and, being aware, therefore, of what the answer should be, expected the dog to cease barking when the number was reached; and that expectation suggested to his own brain the unconscious signal which was caught by the quick eye of the dog. In an analogous manner, a person swinging a button by a thread near the rim of a glass will unwittingly cause it to strike the hour, if he knows the hour, through the unconscious control of his brain over the movements of his finger.

 

Change as a Mental Restorative.—Dr. Joseph Mortimer-Granville, discussing in the "Lancet" the subject of "Change as a Mental Restorative," shows that great discrimination is needed in prescribing this remedy. Some patients there are, such as those who have become wearied with a purposeless life or one of idle dissipation, who have become worn out with change, and to whom a prescription of it for its own sake, without consideration of the circumstances, would only impose an additional infliction. They are most difficult cases to deal with, and demand especial study. The change which a person of this kind requires is "one that will stir a deeper spring of energy than has yet supplied him with motive-force, by compelling his recognition of the responsibilities of life. It is idle to hope that he can be roused to action by the discovery of a new pleasure. . . . The energies of such a character are more likely to be called out by pain and necessity than by pleasure and satisfaction." Some men of pleasure have been delivered from the extreme of ennui, which they had reached, by the loss of fortune bringing pressing need for exertion; but this remedy is beyond the reach of a physician. He might aim, however, to supply an incentive to action by searching for "some inherited seed of ambition or enterprise which has never yet germinated," and may sometimes find it by learning the story of the father's or grandfather's life. A case which came under Dr. Granville's care, and which furnished him with the basis for his remarks on this subject, was cured by the awakening of a strong passion for the breeding of stock, which he had inherited from his grandfather, but which had not been aroused in his nature till he was thrown into circumstances which excited him to emulate the success of a neighbor. A similar case, where no such awakening of energy occurred, ended in suicide.

 

The Mirage on Swiss Lakes.—Professor Charles Dufour communicated to the French Association, at its last meeting, a paper on the mirages of the Swiss lakes, which are often seen between the month of August and the spring, especially in the morning, when the water is warmer than the air. When Monge published his explanation of the mirage, he supposed that the strata of air near the ground were warmer and rarer than the strata above, but he could not prove it experimentally. Professor Dufour has proved it by taking the temperature at different heights above Lake Leman, while the sun was still hidden by the mountains. The mirage frequently produces curious illusions. When a boat is near the point where the ray of light is a tangent to the surface of the water, the mirage of the sky is thrown below the boat, and the latter seems to sail in the air. Seen from Villeneuve, the steamboat plying between Montreux and Vevay seems to be sailing among the vineyards which cover the hills along the shore. When the air, on the other hand, is warmer than the water, as is the case generally in the spring and summer on fine afternoons, the concave side of the refracted ray of light is turned toward the water, and objects are brought into sight which are really hidden by the roundness of the earth. Sometimes the temperature of the different strata of the air varies irregularly. Then the rays of light undergo abnormal refractions which are not always the same for the upper and lower parts of objects. Consequently, the objects are sometimes diminished, sometimes magnified in an extraordinary fashion. Small houses thus distorted are made to look like palaces; their white color is changed into gray by the diffusion of the light, and they are thereby given an air of greater grandeur. Many persons fail to take notice of these mirages because they regard them as reflections from the water; but it is really possible for one with his eye near the water to see the reflection from it of a distant object on nearly the same level. When an image of such an object is seen, it is most probably a mirage.

 

Variations in the Fixed Points of Thermometers.—M, Crafts, in the course of his investigation of the causes of the variations of the fixed points of thermometers, has discovered that glass heated for a long time in the blowpipe-flame shrinks in consequence of an internal change. It is not shown that pressure plays any part in the phenomenon. The particles of the glass which have been separated by the heating do not return to the normal position immediately on cooling, but appear to be in a disturbed condition for some time afterward. The action of heat at a given temperature, say of 670º, by giving a greater mobility to the particles, favors their return to the normal position; but the glass, in cooling from this temperature, retains a part of the expansion which it has undergone. By heating it anew to an inferior temperature, say 570º, we may produce a new diminution of volume, and thus successively, by a very slow process of cooling, bring about the greatest approximation to the normal state, and consequently the greatest stability. The law discovered by M. Pernet for temperatures between the freezing and boiling points of water, according to which the depressions of the freezing-point are proportional to the squares of the temperatures, is not true at high temperatures. A thermometer, for example, which gives a depression of half a degree after a long exposure at 212º, ought, by this law, to give at 670º a depression of 6.8º. The depressions actually observed are much less considerable.

 

The Deep Valley of the Caribbean Sea.—Commander J. R. Bartlett, of the Coast-Survey steamer Blake, has ascertained some interesting facts in regard to the depths of the western part of the Caribbean Sea. The data he has obtained make it probable that a large portion of the supply for the Gulf Stream passes through the "Windward Passage" between Cuba and San Domingo, and that the current extends in it to the depth of 800 fathoms. The temperature, of 3912°, which was indicated at all depths below 700 fathoms in the Gulf of Mexico and the western Caribbean, was not obtained here. Elsewhere, in these seas, the temperature decreased from the surface to 3912° at 700 fathoms or less, and remained constant at that temperature for all lower depths. At greater depths than 600 or 700 fathoms the bottom was always found to be a calcareous ooze composed of pteropod shells with small particles of coral. An immense, deep valley was found to extend from between Cuba and Jamaica to the westward, south of the Cayman Islands, well up into the Bay of Honduras. It has a length of 430 miles, and a general breadth of 105 miles, with a depth nowhere of less than 2,000 fathoms, except at two or three points where the summits of submarine mountains rise to near the surface. Within 20 miles of Grand Cayman it attains an extreme depth of 3,428 fathoms; this island is therefore, to the bottom of the valley, as a mountain 20,000 feet high, and Blue Mountain, in Jamaica, rises 29,000 feet above the bottom, or as high as the highest of the Himalayas is above the level of the sea. The deepest part of the valley has been named the "Bartlett Deep."