Popular Science Monthly/Volume 32/April 1888/Popular Miscellany

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Out-Door Play for School-Girls.—Professor W. E. Anderson, in a paper on "The Physical Side of Education," forming part of the Wisconsin State Board of Health Report for 1887, makes a plea for the indulgence of school-girls in play. He says: "Our school-girls lead a life without play, in the real meaning of the term. Muscular exertion is confined entirely to locomotion, or to movements requiring exercise of the lower part of the body. The restrictions of dress are such that movement above the waist is out of the question. The vital organs are restricted by dress, fashion, and occupations supposed to be suitable to the sex. Notice the difference between the movements of boys and girls of the same age, and attending the same class. While the boys can engage in every species of activity, and practice some sports perhaps too grotesque to be permissible for the opposite sex, the girls of sixteen are satisfied with a stately walk around the block, two under one shawl, conning the next lesson to be heard after school is called. All this is certainly a perversion of what Nature requires. There is no reason why such different dispositions should be manifest between the sexes at this age. The avoidance of play or exercise, and the conventionalities of dress, explain in a large part the want of full and natural development so characteristic of the female sex at the age when they should present in every respect of form, health, and color, the picture of human physical perfection. As it is, the majority of them at twenty years of age are already pale and faded, unnatural in color, wanting in spirit and force, and give evidence of retarded or obstructed development. Where exceptions occur it is usually owing to a violation of the régime of the school. Many of our district schools are supplied with a large, well-lighted, and well-ventilated hall. This hall might be used every day in the week for systematic plays designed or contrived to call into active exercise the senses and the whole muscular system. The running leap of the German gymnasium should form a feature of the sports of this hall. Girls could loosen their waistbands and adopt a style of dress which would enable them to exercise their shoulders and arms. They might find in this practice healthful sport, and a means of developing the tissues of the arms and shoulders, which would result in the development of that beauty of form so highly prized and so frequently simulated by artificial means. The muscles of the hands and arms can be exercised by the play of grace-hoops, cast by the use of two wands, and caught in the same way. The game of shuttlecock, requiring the use of a light bat, alternately in the right and left hand, calls into activity sight and touch. It would not be difficult to contrive games of which young people would not grow weary, and which would without question insure for our feeble school-girls a more durable tenure of good health and a larger stock of force and endurance. While the school ignores the necessity of play to the young, society gives it questionable recognition, and that most potent ruler of society—Fashion—finds in it opportunities for the display of her power. Tennis and archery are resorted to for amusement, and would yield most abundant good exercise were these games not subordinated to such exclusively polite practice that the dress of the players is even one of the chief requisites to the successful conduct of the game. The amusement is captured by the dressmakers and dudes, so that even this means of exercise without flannel suits and rubber soled shoes is not regarded as permissible. As in dancing, the accessories become so elaborate and costly, and beset with so many formalities, that physical recreation is not expected from it. The game merely answers as a scheme to bring people together who are hankering for some opportunity to be near each other, and exchange the sentimental platitudes of unsatisfied and instinctive social emotions. If Gustave and Regina, at fifteen years of age, are to be improved by scurrying about in the manner and time of the modern waltz, then 'twere well that the latter were dressed so as to give her freedom of limbs and lungs, and the recreation given in the afternoon, so that regular sleep at proper time may allow that recuperation of energy and nourishment of wasted tissue consequent upon exertion. As Wesley remarked in apology for the liveliness of Methodist singing, 'It is not right for the devil to have all the best tunes,' so it may be said of dancing, that recreative means should not be monopolized by the social usages and occasions where circumstances exclude the greatest benefit from the exercise, and sometimes induce positively injurious consequences."


What is a Glacier?—The Philosophical Society of Washington, some months ago, had a symposium on the question "What is a Glacier?" Mr. I. C. Russell, taking both the Alpine and continental types into consideration, would define a glacier as an ice body, originating from the consolidation of snow in regions where the secular accumulation exceeds the loss by melting and evaporation, or above the snow-line, and flowing to regions where loss exceeds supply, or below the snow-line. Mr. S. F. Emmons described a glacier as a river of ice, possessed, like the aqueous river, of movement and plasticity. The nevé field is the reservoir from which it derives not only its supply of ice, but the impulse which gives it its first movement. Mr. W. J. McGee held that the phenomena of glacier ice and nevé ice appear to belong to a graduating series; and in consequence the two phases can only be arbitrarily discriminated. Mr. W. H. Dall defined a glacier as a mass of ice with definite lateral limits, with motion in a definite direction, and originating from the compacting of snow by pressure. Mr. T. C. Chamberlin, disclaiming attempts to give a rigorous definition, thought the better distinction between nevé and glacier was genetic. There is an area of growth and an area of waste in every glacier. Superficially the area of growth coincides with the nevé; the area of waste with the glacier proper. Mr. C. E. Button said there was little difficulty in recognizing a glacier when all those features that characterize it are present, and where the conditions are of the ordinary nature; but exceptional cases arise to make an exact definition impracticable.


The Beauty of Old Wrought-Iron Work.—Mr. J. Starkie Gardner has observed, in a Society of Arts lecture on "Wrought-Iron," that old iron-work possesses interest and attractions which few examples of modern work can equal. This is partly because, estimating by the eye and working his scrolls by hand, the workman "produced an irregularity and play in even the most monotonous design which is artistically charming to us, but was perhaps even a source of chagrin to him." The modern smith works in a different way, and turns out uniform rods and scrolls, while he considers any irregularity a sign of bad smithing. The scarcity of straight bars among the oldest examples was probably due to the fact that it was extremely hard to handle a long bar and beat it out perfectly true with mathematically exact and sharp angles. Another element of artistic superiority in the older work lay in the fact that it was intrusted only to persons who had a special aptitude; and, if such a person were not forthcoming, the work was either not executed, or was made in the simplest form; while, if he were at hand, the details of the design were left to his fancy, and were, therefore, well within his own powers. It was the existence of the skilled smith that created the demand, rather than the demand that created the smith; and it seems a reasonable inference that none such had to beg for work in the middle ages. When a grill was wanted for, say, Westminster Abbey, it was not the local man who had the commission, but a smith from wherever he might be found, who had a designing capacity and a skill of his own, who was fetched and maintained until the task was completed. The smiths of those days were probably not fettered by estimate or bound by time; but, we have a right to suppose, the art-work was produced for art's sake by a genuine artist.


New Kinds of Optical Glass.—Professor Abbé, of Jena, has been experimenting for many years with a view to produce an optical glass which should be free from the defects incidental to all silica glasses. In particular, he sought to produce a higher degree of achromaticity than was hitherto possible, by diminishing the secondary coloring effects inseparable from the ordinary silicate flint and crown glasses, and to produce a greater multiplicity in the gradations of optical glass in respect of the two great constants of the index of refraction and the mean dispersion. In silicate glasses, those two constants increase and decrease together. Cases often arise in which a different relation is desirable. Professor Abbé has produced glasses in which both objects arc fulfilled. He has produced achromatic lenses of a more perfect kind than were ever before obtainable, and has introduced a whole series of new glasses of graduated properties. These glasses are offered freely to the trade without any restriction or patent being allowed to stand in the way of further development.


How the Krakatoa Dust was carried.—Mr. Ralph Abercromby introduces an account of his studies of the relation of the upper wind-currents near the equator, with the diffusion of Krakatoa dust, by showing that, as a rule, there is a continuous successive veering of the equatorial winds as we ascend. Standing with one's back to the surface wind, the upper currents will—north of the equator—come successively more and more from the left with increasing height; south of the equator, the rule is reversed. Nevertheless, some remarkable variances have been observed in the region between the equator and the doldrums. From the I consideration of these exceptional cases the author concludes that when the trades or monsoons meet they do not interlace, as has been suggested by many, but the upper winds combine in a generally easterly current, and probably diverge only slightly pole-ward on either side. The velocity of this current is unknown. Applying this theory to the dust-flow from Krakatoa, as its advance was indicated by the view of green suns and red after-glows, the system of its movement will appear to have been very simple. "The great dust-stream was carried for the first twenty-four hours by the normal easterly upper currents over the southeast trade, at the extraordinary rate of more than one hundred and twenty miles an hour, but hardly extended north of the line. . . . In fact, we may say that the great stream of Krakatoa dust was carried nearly round the world by the usual upper winds of the southeast trade, in which the dust was first ejected at a rate of about one hundred and twenty miles an hour, and that the dust spread very slowly either north or south of the main current." The high velocity of one hundred and twenty miles an hour is certainly more than would have been expected; but, while we have very few observations of the rate of motion of the highest clouds, a number of those that we have give figures approaching this speed. So that the author is able to add: "There would be nothing, then, outrageous in the assumption of a velocity of one hundred and twenty miles an hour for the easterly current over the equator to account for the high speed of the diffusion of Krakatoa dust; and it is also satisfactory to know that the general direction of the flow is in accordance with the most recent researches on the vertical succession of the upper currents near the equator."


The Crater-Lake Chala.—Mr. J. A. Wray last year reached the edge of the water of the crater-lake Chala, on Mount Kilimanjaro, which Mr. Thomson saw and has described in his account of the mountain. The lake is about three miles long by one mile wide, with banks so steep that a descent to the water is impossible, except at one place on the western side. Mr. Wray found the water clear, cool, and perfectly sweet, though the lake has no apparent inlet or outlet. It contains fish, and numerous water-fowl were swimming on its surface, the flapping of whose wings, when they took to flight, produced a sound, through confused reverberation in the deep, well-like basin, like the rushing of a distant railway-train. The steep banks, about one thousand feet in height, are well wooded, and vegetation clothes their surface down to the water's edge. There is no mark cf higher water, and it probably keeps the same level all the year round. The cries of birds had a peculiar sound, and Mr. Wray believed that it is these noises that have given rise to the native myth that a Masai village formerly stood here, which was swallowed up by the lake. The people of Taveta believe that they hear voices, the lowing of cattle, etc.


Black Bears.—Mr. William Pittman Lent gives an interesting account of the "Black Bear" in the "Transactions" of the Ottawa (Canada) Field Naturalists' Club. The young of bears are produced in March, and no female has been killed by Canadian hunters, before or after the hibernating season, that showed any evidence of being in the gravid state. The cubs are very small—not larger, when two days old, than kittens of the same age. The animals feed principally on vegetable food—grapes, roots, berries, beechnuts, oats, and Indian corn. They sometimes visit the oat or corn fields before sunset, and may be taken there by a skillful hunter. They are inordinately fond of honey, and they feast luxuriously in the fall on the berries of the mountain-ash. When their natural food is scarce they visit the farm-yard and carry off pigs and sheep, and will even kill young cattle when pressed for hunger. They are also fond of fish; they have been known to wade and swim in the rivers for the purpose of catching them, and are frequently to be seen along the coast of the island of Anticosti, devouring herring-spawn. They are active, though clumsy, and will run for a mile or two with astonishing speed. When closely pursued by dogs, a bear will take to a tree, up which he can climb rapidly, but from which he descends more slowly, head upward, as soon as it appears safe to do so. They are very shy and timorous in the presence of man, and will make off rapidly when they perceive a human being by sight or scent, but they are most affected by the scent. The black bear fights with teeth and claws, and by hugging. When in an erect position he is a perfect master of the art of self-defense, and it would puzzle a pugilist to get in a blow at him. His most vulnerable part is the nose, which is provided with many sensitive nerves intimately and directly connected with the brain. When a bear is standing on all-fours, there would be no difficulty in striking him with a club; but, when he is sitting erect, it would be an entirely different matter. In Canada black bears retreat to their dens—generally under the roots of large trees, or occasionally in rocky caves—at about the setting in of the season of confirmed frost and snow. They remain there in a quiescent state, although not—as has been well established by hunters who have killed them in their dens in the depth of winter—in a trance-like condition of torpidity, till the opening of spring. When they first emerge from their four months' slumber they are heavy and fat, and their fur is in prime condition, but shortly afterward they fall off in flesh, and soon become ragged in coat and lanky in appearance. Toward October, if they have had a favorable summer, they are found in good condition, and at any time after the middle of November their skins have the finest color, and the thickest and heaviest coat of fur. Bears are still found within eight or ten miles of the city of Ottawa. Even the black bear, Mr. Lent thinks, is of sufficient importance in the economy of Nature and of man to entitle him to legal protection.


Useful Reptiles.—When we have secured protection to the birds, it will be time to teach the people to have more mercy on the reptiles. The popular, almost unconquerable prejudices against this class of animals are regarded by science as mistaken except as to a very few kinds, but the public still need enlightenment on the subject. Professor O. P. Hay has embodied a popular lesson on the innocence and even value of most reptiles in his paper on "The Amphibians and Reptiles of Indiana," which, being comprised in the State Agricultural Report, will reach all the inhabitants of at least one commonwealth. "Many amphibians and reptiles," he says, "are of direct value to man. Many, as various kinds of turtles and frogs, are used as food, and such might even be profitably bred for that purpose. Many others are useful because of their propensity for devouring insects, mice, and rats, that are the pest of the farmers. A few, indeed, are dangerous; but it is worth any person's while to study our reptiles, if for no other reason than to be freed from constant fear of them. Of nearly a hundred species of amphibians and reptiles to be found within Indiana, not more than three or four are poisonous, and these are of rare occurrence. . . . Some others may strike, or bite a little, or constrict, as they have a right to do, but they are not venomous, and can do little hurt. Snakes that roll along like hoops, snakes that blow poison, snakes that sting with their tongues or the tips of their tails, and snakes that live for weeks in people's stomachs, are creatures of the imagination. Therefore, considering their usefulness as destroyers of vermin, no amphibian or reptile ought to be killed, unless it is to be employed for practical uses or preserved as a specimen for scientific purposes. . . . If the boys of the country are to be allowed to shoot all the birds and stone to death all the reptiles, we may yet be compelled to surrender to the vermin."


How the Glacial Drift was deposited.—The manner in which the glacial drift was deposited by the great ice-sheet has been studied by Professor O. P. Hay as a problem whose solution has not yet been effected. One of the difficulties in the way of comprehending it originates in the fact that all our analogies are derived from the observation of modem glaciers in motion down steep inclines, while we do not fully recollect that the great glacier in question most probably came to a standstill in level territory. Bearing this point in view, the author concludes that a glacial ice-sheet moving over a nearly level surface would possess far less power of abrading its bed than the same glacier would have while descending a slope of high angle; through subsidence of the glacial mass, caused by the earth's heat, and through other influences, a constantly increasing proportion of inert materials would collect in the lower layers of the moving ice; the accumulation of such materials would tend to retard the motion of the lower portions of the glacier, and, finally, when they formed a sufficiently great proportion of the mass, all motion of the lower portion would cease, and a permanent deposit would begin and continue to be made; other masses of detritus might be deposited at the foot of the glacial ice-sheet as a terminal moraine, and still other masses on the top of the already formed deposit when the glacier finally melted.


Mineral Constituents of Food.—In considering the different foodstuffs, says Dr. N. A. Randolph, we must regard water as of prime importance. In the average adult it constitutes from fifty-nine to sixty-five per cent—or even larger proportions, according to other estimates—of the entire weight. We must regard it as an essential condition for the manifestation of all total phenomena. Certain solid inorganic elements of food are also essential to the well-being of the organism, for in their absence the tissues can not be properly built up, nor can the processes in either the solids or the fluids of the body go on. The presence of mineral constituents appears absolutely essential to the integrity of proteid matter, and their withdrawal entails a loss of most of its distinguishing characteristics. A striking illustration of the necessity of this class of food-stuffs, and of the disturbances resulting from a very slight diminution in the amount of inorganic constituents present in the economy, may be found in the recent experiments of Ringer. Minnows, which thrived in brook-water, and remained alive in it without food for many days, died in a few hours when placed in distilled water properly aërated. Examined more closely in detail, the inorganic elements of food consist of the salts of the alkalies, salts of the alkaline earths, iron, silica, and fluorine in various combinations. The importance to the economy of the carbonates of the alkalies, and therefore the importance of fresh vegetable food from which they are most readily elaborated, must not be underestimated. Of the uses of potassium chloride but little is known. Sodium chloride, however, or common salt, has been more closely studied. In such proportions as the healthy taste demands, it is undoubtedly a valuable stimulant to the nutritive processes. The extent of the need for lime-salts in young animals is surprising. Iron is undoubtedly a food; for the quantity in the system is restored as fast as it is eliminated. Contrary to popular belief, the major portion of the iron of the human body is found, not in the blood but in the muscles, even after their contained blood has been removed. Silicic acid is found in very small quantities in bones, hair, and blood. It is supplied by many vegetable foods. Calcium fluoride is found in teeth, and to a slight extent in bone. Fortunately for us, these inorganic foods, whose withdrawal exercises deleterious influences on the economy, are, as a rule, present in great quantity in the actual foods in a mixed diet. In certain methods of preparing foods, however, their proportion is much diminished; thus, in the boiling of meats and vegetables, a large quantity of these important foodstuffs is extracted. Indeed, one of the chief dietetic advantages of salads and uncooked vegetables in general is, that these elements have not been removed.


Why do our Teeth decay so fast?—To this question Dr. Julius Pohlman answers, because we do not use them enough—showing that as a rule "those people who are least acquainted with the so-called hygiene of the teeth are the happy possessors of the soundest dentition"—like the negroes who chew sugar-cane, the German peasants, who are famous for their brilliant "Schwartz-brot-Zähne," or "rye-meal-bread teeth," polished but not worn out by daily mastication of dry, hard, black loaves, and the few old people left among us who persist in eating bread-crusts. Our weak and effeminate teeth are not used to hard work, and, like other organs that are not exercised, tend to atrophy. "The foundation for bad teeth," says this author, "is generally laid in early childhood; for numberless mothers and nurses very carefully soften the food or remove the crust from the bread before giving it to the little folks, because it may otherwise 'hurt their teeth,' and so the child grows up with a set of unused organs in its mouth; and when we have finally succeeded by the creation of artificial conditions in producing weak organs, then we wonder why the poor child has such bad teeth, and why it is so often suffering with toothache, and why the dentist's bill is so high. Teeth are organs specialized to perform the work of mastication; they are subject to the same laws that govern other organs, and their strength is determined by their use. Understanding this, we are obliged to admit that, if we ever become a toothless race, it will be our own fault."


Antiseptic Properties of Coffee.—The stimulating effects of the infusion of coffee have been referred to its excitant and tonic properties. Recent researches indicate that it has still more valuable qualities—those of an antiseptic. In 1885 M. Oppler announced the property which it possesses of preventing, to a certain extent, the development of micro-organisms in substances liable to putrefy. Then M. Sucksdorff showed that infusions of coffee and of tea might remain exposed openly to the air for a considerable time without molding or developing bacteria. Finally, Mr. Heim has recently published the results of more exact researches, which tend to demonstrate the reality of the antiseptic properties of roasted coffee. The cholera bacillus appears to be one of the organisms most readily affected by coffee. It is desirable to have the investigation extended to the infusion of tea, which will probably be found to have similar properties.


A Crystal Skull.—Among the interesting features at the meeting of the American Association was the exhibition, by Mr. George F. Kunz, of a crystal skull which had been brought from Mexico by a Spanish officer before the French invasion, and, having been in possession of Mr. Evans, the English collector, and Mr. M. E. Boban, now belonged to Mr. George H. Sisson, of New York. The inclusions in the rock-crystal material were identical with those in the quartz or rock-crystal from Calaveras County, California. Nothing more than this is known of the origin of the skull. It is not Chinese, or nature would have been more faithfully copied; nor European, for the work would have been more carefully finished. Professor Morse, who has resided in Japan, and Mr. Tatin Basha, a Japanese, aver that it is not of that origin, Mr. Basha remarking that a skull is not considered a fit decorative object in Japan. Large masses of crystal have been found in the California locality, and small skulls made of the same material, measuring rarely more than two inches across, have often been brought from near Pachuca, in the State of Michoacan, Mexico. The skull weighs one hundred and seventy-five and one quarter ounces. The eyes are very deep hollows. The line separating the upper from the lower set of teeth has evidently been produced by a string, either held in the hand or stretched across the bow, and is very characteristic of Mexican work. The skill of these people in making such objects has been questioned, but the large masks, mirrors, and other articles of obsidian; the objects of agate, and the numerous jade and jadeite ornaments; and the fact that they made small skulls of rock-crystal and skulls inlaid with turquoise—to the fashioning of which the making of this skull was as nothing—all indicate that they might have made a large skull if a suitable stone came into their possession. Since they procured their turquoise from Los Cerilles, New Mexico, why should we doubt that they were acquainted with the California locality for rock-crystal?


The Nest of the "Purse-Web" Spider.—Among the natural-history papers read in the British Association was one by Dr. H. C. McCook, describing the nesting habits of the spider Atypus niger of Florida, a species which it has been found was first observed and figured, as the "purse-web spider," by John Abbott, in 1792. The nests of the Atypus are silken tubes of close texture and various lengths and sizes, which are spun against the bark of trees in nearly equal proportions above and below the surface of the ground. Some of the tubes are from twelve to fourteen inches long, and from one half inch to three quarters inch in diameter; others—the nests of the young—are a few inches long and of the thickness of a pipe-stem. The inside of the nests is white and clean; the outside is weather-stained and covered with sand. In spinning these tubes the spider first stretches a series of straight threads from a point on the bark about an inch and a half above the ground. These lines are more or less approximated, and present the appearance of a rough framework for the tube. Upon them the architect places a thickening of spinning-work, which is beaten down and spread over by the long spinners, the process resembling more that of a plasterer than of a weaver. The work is done in small sections, until the original frame is quite covered in. The lengthening of the tube is accomplished by adding to the original section until the desired length is attained. The new-made tubes were found covered on the outside with sand. The spiders were not seen in the act of sanding their nests, but a similar habit in Atypus piceus of England has been observed and described by Mr. F. Enock, who has discovered that the sand is forced through the texture of the web from the inside. The idea of mimicry has been advanced in connection with this nest-sanding. Certainly the tube does closely resemble the tree to which it is attached. But Mr. Enock's observations indicate that the spider has taken a convenient way of getting rid of the sand brought up by its mandibles from the excavations of its burrow below the surface.


Insects resembling Minerals.—Mr. Edward B. Poulton, discussing the resemblances which certain insect-pupæ seem to bear in color to the surface on which they; are found, thinks it probable that the gilded I pupae of Vanessidæ (butterflies) resemble glittering minerals, like mica, which is very common in many places. Their shape is very angular, and like that of minerals. Conversely, the gray pupæ resemble gray and weathered rock-surfaces; and the two conditions of rock would themselves act as a stimulus for the production of pupæ of corresponding color. The power was probably gained in some dry, hot country where mineral surfaces do not weather quickly. Once formed, it may be used for other purposes, and in certain species probably conveys the idea to enemies that the insect is inedible. It is interesting to note how the Vanessidæ, primarily colored so as to resemble mineral surroundings, are modified for pupation on plants.