Popular Science Monthly/Volume 29/July 1886/Popular Miscellany

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Popular Science Monthly Volume 29 July 1886  (1886) 
Popular Miscellany
 

POPULAR MISCELLANY.

The Chicago Public Schools. Mr. James R. Doolittle, Jr., President of the Board of Education of Chicago, in his report for the school year 1884-'85, considers briefly but with vigor many interesting points in connection with the school system of that city, which are well worth the attention of school officers generally. He regards the school as a progressive institution, which should look to the future rather than to the past, and, while it takes advantage of all that has been gained, should be on the watch to discover whatever may help to make it more efficient in accomplishing its object—which should be to give youth facility to adjust themselves to the duties and exigencies of life.

The board has determined that every one of the grammar-schools shall have a library, concerning the constitution of which the President remarks: "None of the books should be beyond the ordinary capacity of grammar-school children. In fact, they should be much easier to comprehend and master than the other books of the course, otherwise the library would fail to attract the children. None of the books should contain anything the children ought not to read, and none should be so difficult that they may not be read with pleasure and interest." The president is justly alarmed at the increase of near-sightedness with the advance of age in the school, the rate of which is shown to rise in Chicago from 4·09 per cent at six years of age in the Ogden School to 27·08 per cent at twenty years in the North Division High-School; but he can suggest no remedy except improved lighting and the most legible text-books. Concerning "practical education," a wholesome conservatism will serve as the sheet-anchor of safety. . . . The principal object of education is to instruct the pupil how to learn; to enable him to comprehend, in a way, the new things which encounter him when his school days are over. Up to this point, which, in the case of the child educated in the common school, will never be very high in an educational aspect, all the pupils should go, boys and girls alike. Drawing and book-keeping in its simple form might well be taught, for they are useful to every one. It is lamentable that nothing is taught, short of the high-school, concerning the organs and functions of the human body. A considerable portion of the work required of the pupils appears highly artificial, and of questionable utility. A tendency is observed to teach a mass of unimportant facts, which the pupils will certainly, and had better, forget, and a disposition to compel them to absorb and assimilate ideas beyond the ordinary comprehension of childhood. These things "may furnish an opportunity for precocity to shine, but do not facilitate the normal development of the intellectual powers." The practice of ascertaining the relative standing of pupils by the rapidity with which they answer questions, or perform certain operations, is highly unjust and fallacious. " The standing of pu- pils should be established by the degree of thoroughness attained in their respective acquirements; that is the test of men in practical life, and it should be the same in school-life." The higher mathematics and the dead languages have received too much attention, because the fruits are of meager value and limited utility ; but " more time should be spent in our schools in giving in- struction in English words and expressions." The standard of English study should be raised everywhere.

Principles of Sea-Bathing. Sea-bath- ing, when properly and carefully indulged in, is a most health-giving and enjoyable diversion. But a few broad principles should be remembered. Never bathe within two hours of a meal, never when overtired and exhausted, and never when overheated. At the same time the body should be warm, and not cold, when you plunge in. Do not remain in the water long enough to become tired or chilly, and when you come out dress quickly. It should also be remembered that bathing does not agree with everybody. Those who feel faint or giddy in the water, or whose hearts begin to beat overmuch, should consult a doctor who is thoroughly acquainted with their constitutions, before they enter the water again. Medical papers say that many of the bathing fatalities which have been generally attributed to " cramp " are really due to failure of the heart's action, induced by the plunge into cold water, and aggravated by swimming. A good result of the bath ought to make the bather feel warm and fresh. If, instead, shivering and cold ensue, harm is being done. Children should not be forced into sea-baths, for their reluctance may be oc- casioned by some constitutional drawback, testifying that the process is harmful to them.

Tfee American Economic Association.

The American Economic Association has been founded by the co-operation of a num- ber of students of that subject, for the en- couragement of economic research, with the publication of monographs and the promo- tion of perfect freedom of discussion. It starts with the belief that political economy

��as a science is still in an early stage of its development ; that its advance is to be sought through the historical and statistical study of actual conditions of economic life rather than through speculation. It recog- nizes that the conflict of labor and capital has brought into prominence a vast number of social problems, whose solution requires the united efforts, each in its own sphere, of church and the state. "Without taking any partisan attitude in the study of the in- dustrial and commercial policy of govern- ments, it believes in a progressive develop- ment of economic conditions, which must be met by a corresponding development of legislative policy. Among the topics which are suggested as proper subjects for reports by the standing committees, are the employ- ment of women in factories ; municipal finance ; rent in the United States ; the National Railroad Commission ; limitation of suffrage as a remedy for abuses in local administration ; the effect of transportation on the laborer; and the silver question. The President of the Association is Dr. Francis A. Walker, of the Massachusetts Institute of Technology; the Secretary is Richard T. Ely, Ph. D., of Johns Hopkins University.

Parsce Funerals. As soon as the case of a Parsee about to die is seen to be hope- less, he is washed all over in gomez (ox's urine), and dressed in clean clothes, while the priests repeat prayers and Avesta texts. When life is extinct, the feet are tied to- gether, the hands are joined, and the body is laid on the ground-floor. A priest re- mains by it, saying prayers and burning sandal-wood, till the bearers come to take it to the dakkma, or "tower of silence." As soon as the bearers arrive, the seven parts of the Ahurian hymn are chanted, to combat the power of death, which has come from hell to seize the corpse and threaten the living. When this is over, the body is taken off by the bearers on an iron bier to the dakfana, where it is exposed, " clothed only with the light of heaven," to the vult- ures, which will strip it to the skeleton in about an hour. The skeletons soon become perfectly desiccated, and are then thrown into the deep central pit of the tower, where they crumble and are washed away by the POPULAR MISCELLANY.

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��rains. The object of exposing the bodies in this way is said to be to avoid pollut- ing the earth by burying them. Through- out the Zoroastrian writings that remain, this principle is continually dwelt upon. Cremation is even a greater crime than in- terment of the dead, because, it was alleged, of the exceeding holiness and purity of fire, which must not be polluted. These views, it has been suggested, originated in the ab- horrence of primitive Zoroastrianism for cannibalism and human sacrifices, on ac- count of which it surrounded the dead hu- man body with such awful horrors and ob- servances as should effectually defend it against them.

The Flying Force of Birds. Dr. Karl Miillenhoff has published, in the proceedings of the German Society for the Advancement of Aeronautics, a paper on the force exerted by birds in flying. The latest calculations, by Marey and others, give the maximum force exerted by birds at 1*2 to 1"4 kilo- gramme per square centimetre of muscular section numbers that are not greater, but rather less, than those which represent the strength of other animals. Dr. Miillenhoff deduces from his own calculations that the labor performed by the wing in any time- unit is little if any greater than that in- volved in walking on the ground. This re- sult agrees with the facts shown by experi- ments that the weight of doves was not changed after considerable test-flights ; and that it fell off only a few grammes after a flight of three or four hundred kilometres. Quite different from this are the results afforded by the experience, say, of veloci- pedists ; one of whom confessed to the au- thor that he had lost ten pounds after a few months of cycling, and who suffered after an hour or so of his exercise from a greatly quickened pulse and an intense heart-beating. Prechtl, of Vienna, some years ago published the conclusion that the force exerted by birds in changing their place was not greater than that of the other animals, and that the amount of force ex- erted by large and small birds was rela- tively the same. Helmholtz, twenty-seven years later, came to an opposite conclusion which he based, however, only on theoreti- cal grounds. He predicated a geometrical

��similarity in the forms and movements of smaller and larger animals, and that a great- er increase in power must be given the larger animals to overcome the greater re- sistance they have to encounter. Dr. Miil- lenhoff having subjected this theory to an experimental test, has found it not sound. The geometrical similarity of motions does not exist. While the wings of the larger birds move up and down, those of the smaller birds move diagonally, and of the smallest nearly horizontally. The author having also examined the rate of increase of velocity corresponding with increase of size, separately as regards vertical and hor- izontal movements, finds that increase in the weight of' the body is not accompanied by increase in the relative muscular mass ; that the amount of absolute force does not increase as the bird becomes larger; that no differences are apparent between birds of different sizes in the velocities of the muscular contractions; and that, regarding differences in the quantity and quality of the food consumed by the larger and smaller \ birds concerning which there is question I while the labor performed in flight can be furnished only at the expense of a corre- sponding consumption of chemical elasticity, j we can so far not make any definite decla- ration concerning either the amount of substance consumed in flight-work, or the amount of food required to compensate for the substance that is consumed.

The Problem of the Irrawaddy. Mr.

Robert Gordon, who has recently addressed the Royal Geographical Society in support of his theory that the Irrawaddy is the outlet of the Sanpo of Thibet, says that that river presents the greatest geographical problem in Asia. Mr. Gordon's view is contradict- ory of the opinion generally held by geog- raphers that the Sanpo is the Brahmapoo- tra, a river that it must meet or run around before it can reach the Irrawaddy. In favor of his theory, he adduces the testimony of a number of Thibetan and Chinese authorities, dating from times of considerable antiquity ; the size of the Irrawaddy in its upper course, which can not be supplied by the few small streams and the limited water-shed the geog- raphers give it ; the testimony of the names of various rivers and branches of rivers in

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��THE POPULAR SCIENCE MONTHLY.

��the debatable region ; and the opinion of a number of geographers and travelers who do not agree with the majority. Moreover, the Brahmapootra does not need the San- po, and the Irrawaddy does. Mr. Gordon's views were strongly controverted by General J. T. Walker and other experts in Indo- Chinese geography.

Distribution of an Insect Species. The

Anonia plexippus, an American butterfly, is now engaged in distributing itself over the world. It is extending itself both east- wardly and westwardly. Its natural range appears to be from the Hudson Bay Ter- ritory to the Amazon and Bolivia ; but some thirty or forty years ago it began to wan- der. It has established itself and become abundant in the Sandwich Islands. The first specimens were observed in the Mar- quesas Islands, by a Roman Catholic mis- sionary, about 1860. It is now the com- monest butterfly there. It has appeared in the Society, Cook, Harvey, Samoan, Friendly, and Feejee Islands, the North Island of New Zealand, Norfolk Island, Australia, Tasma- nia, the New Hebrides, Solomon Islands, New Guinea, Celebes, and Java ; and it was abundant in New Caledonia a few years ago, but has become more rare there. In the eastward direction it has made its way to the West Indies, has been long estab- lished in Bermuda, furnished one specimen in the Azores in 1864, was found in South Wales in 1876, at La Vendee the only specimen yet found on the Continent of Europe in 1877, and in Kent in 1881.

Uses of Liqnid Carbonic Acid. The

liquefaction of carbonic acid was at first a mere scientific curiosity, and only a few are probably as yet aware that it is much more. But a German firm, Messrs. Raydt & Kun- heim, have devised an apparatus for pro- ducing the liquid, and are producing it in large quantities for industrial purposes. It is used for charging beer in the cask ; and in the manufacture of seltzer-waters the gas is more easily and effectively introduced from a vessel containing the liquid than in the old-fashioned way. It has been found very valuable for the service of fire-extin- guishers. The Krupps, of Essen, use it for producing compact castings. For this pur-

��pose the mold is closed as soon as the metal has been introduced, and is connected by a valve with the vessel containing the liquid acid, the pressure of the gas from which is augmented by heating it in a salt-water bath. The Krupps have found that a heat of 360 will give the colossal pressure of twelve hundred atmospheres. Another ap- plication of the liquid proposed by Dr. Raydt is to the raising of sunken ships by means of the gas from it. Compressed air has long been employed for this purpose, but it requires a costly apparatus that may be done away with if liquefied carbonic acid is sub- stituted for it. In some experiments made at Kiel, a stone weighing three hundred quintals was raised, by means of a balloon filled with carbonic acid, from a depth of thirty feet to the surface of the water in eight minutes.

Travel by Balloon. Mr. William Pole insists, in '* Nature," that the feasibility of balloon navigation has been made very highly probable by the recent French ex- periments. M. Tissandier, in 1883, obtained with his dirigible balloon a velocity of nine miles an hour. The French military authori- ties then commissioned two of their officers, Messrs. Renard and Krebs, to work the prob- lem further out. They obtained an independ- ent velocity through the air of upward of thirteen miles an hour, with a balloon which was managed, steered, and guided with the greatest ease, and was made to return to its starting-point in defiance of the wind. Care- ful calculations, made according to the rules of M. Dupuy de Lome and Professor Ran- kine, of the resistance afforded by the air and the efficiency of the screw-propeller, show that the attainment of considerably higher speeds is perfectly practicable. A balloon of fifty feet diameter, for example, would carry power sufficient to give a speed of upward of twenty miles an hour, and still leave a considerable buoyancy disposable.

Colors of Swedish Eyes. Professor Wittrock read a paper before the Swedish Anthropological Society on the investigations into the hereditability of the color of the eyes, which he had undertaken at the in- stance of Professor Alphonse de Candolle. These results differed from those which

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��Professor de Candolle had published for Switzerland, North Germany, and Belgium. Brown eyes were more common among women than among men. From the fact that 56 per cent of the children of par- ents who were bi-colored (or one of whom had brown and the other blue eyes) had brown eyes, it appeared that eyes of that color were on the increase. The majority of wives had brown eyes. The average number of children of con-colored parents was 4*49, and that of bi-colored parents 4-03 contrary to Professor de Candolle's observations, which gave the larger number to bi-colored parents. It also appeared that 52*6 per cent of the children inherited the eyes of the father and 47*4 per cent those of the mother; of the sons, 51*8 per cent inherited the father's, and 48*2 per cent those of the mother, while the figures with regard to the daughters were respectively 53*5 and 46 - 5 per cent. These figures show that in Sweden the eyes are not predomi- nantly inherited from the mother alone, and that the offspring of equally constituted par- ents should not be weaker than they. Chil- dren under ten years of age were excluded from the examinations, and blue-gray and gray eyes were classified as blue.

Causes of the Extinction of Species.

Professor A. S. Packard has published an article in the "American Naturalist" on some of the apparent causes of the " Geo- logical Extinction of Species." He reviews at length the factors of changes of climate to which he ascribes the most extensive phenomena of the kind. In the palaeozoic ages, the climate of the whole earth was nearly uniform, and species were very widely diffused. Upheavals of mountain - ranges and continental masses, taking place at dif- ferent epochs, produced more or less marked differentiations and local conditions favor- able to some species and unfavorable to others, with the result that some flourished while others declined and faded out. The glacial epoch, bringing great changes of cli- mates, produced also many revolutions in the relations of species. Changes in alti- tudes, marked on the American Continent by the elevation of the Rocky Mountain and Andean districts to from five thousand to ten thousand feet, the workings of which

��are still going on to a certain extent, also materially affected those relations ; and similar changes have occurred in the other quarters of the world. "The biological changes were not due to climatic and geo- logical changes alone, but it should be borne in mind that the great changes, slowly in- duced, but not without striking final results, ending in the addition or loss of vast areas of land, induced extensive migrations, the incursions of prepotent types which exter- minated the weaker. The reaction of one type of life upon another, the results of nat- ural selection, were apparent all through ; but these secondary factors were active both during periods of quiet and periods of change. . . . Local extinctions due to local changes of level ; the formation of deserts, saline wastes, and volcanic eruptions and vast outpourings of lava, such as took place in Oregon and Idaho during the Tertiary, with submarine earthquakes causing the death of fishes on a vast scale, these are quite subordinate factors."

Toad-Lore. Toads have much in com- mon with frogs, but they are. hatched from spawn that is deposited in long strings, while frog-spawn is in masses, and they have no teeth. They are also marked by ugly warts, which give out an acrid but not poisonous juice. They have tongues whose motions, nearly as quick as light- ning, the eye can not follow, and which sweep in the insects they catch with such speed that the victims " seem to melt into thin air" rather than to be caught and swallowed. They can climb plastered and whitewashed walls or flights of steps, and even into flower-pots whose outward sloping sides would seem to forbid such an achieve- ment. They will eat nothing that is not in motion except their own skins, which, when they are cast off, they roll up and swallow. The muscles of their thighs and legs strik- ingly resemble those of man. They can not breathe when their mouth is held open. The old necromancers used them freely and in various ways in their magic. In some parts of England the application of a toad is supposed to stop bleeding, and dried specimens are worn as charms against rheu- matism. The members of a Devonshire family had a reputation for curing " king's

�� � evil " by means of toads. Some of the Ger- man peasants are said to have a way of cru- cifying toads, which must be caught for the purpose on Easter-Sunday morning before sunrise; then burying them in an ant-hill, and leaving them there till Whitsunday, when their clean and white bones, worn in a little bag around the neck, will always make the possessor win in games of chance. The Thibetans, according to Abbe Hue, tell of a toad that dwells amid the mists of a lofty mountain-range, and, unless he is propiti- ated, flings ice and avalanches down upon those who pass in the valleys below.

Cuban Storms. The "Meteorological Annual " of the Royal College of the Society of Jesus at Havana, for 1875, which has only recently been published, contains several instances of coincidences between Cuban storms and meteorological phenomena in the United States, and particularly of seem- ing relations with magnetic manifestations. During three days in April 3d, 4th, and 5th a " norther " prevailed, and was suc- ceeded on the three following days by a re- markable magnetic perturbation, which was accompanied with a high barometer and a strong wind, with daily manifestations of aurora in the United States, but without accompanying electric phenomena. A mag- netic perturbation on the 13th of April was coincident with a norther, much thunder and lightning, a very heavy rainfall and a dis- position and state of the aqueous vapor which gave rise to solar and lunar halos, and other optical effects ; but during the time no auroras were reported from the United States. Father Vines, the compiler of the "Annual," points out various other re- lations between the magnetical and meteor- ological phenomena which suggest that this line of inquiry is likely to lead to valuable additions to our knowledge of weather- changes. The diurnal and seasonal fluctua- tions of the barometric column in their varvins; amounts are significant in their re- lations to the analogous phenomena in the United States and over the high-pressure | area of the Atlantic. For four days previ- ous to the observation of the highest tem- perature of the year July 30th, at 4 p. m., 98*8 auroras had been observed in the United States, and the magnetic and elec- trical conditions showed marked disturb- ances at Havana. Of eighty recorded thun- der-storms, sixty-five occurred during the five months from May to September, and only three during the four months from January to March, and December. This al- most total absence of thunder-storms from the rains of the winter months, as compared with the summer months, when lisrhtninjr or some other electric phenomenon occurs almost daily, is important in its bearing on the theory of the thunder-storm.

A Xew Species of Box-Wood. A new

species of box-wood has been discovered growing in the neighborhood of the Cape of Good Hope and in Caffraria, and a quan- tity of it has been sent to the English mar- ket. The first sample specimens that were sent were marred by defects in the grain, which made them of inferior quality for engraving purposes. A second and larger lot appears to promise better, for it is said of it that the logs are of good sizes, sound, and clean grown. The wood possesses a closeness equal to the best Abassian box- wood, and it is thought will suit admirably for engravers' purposes. It appears to be one of the best hard woods that has yet been put forward as a substitute for genuine box-wood. The new species very closely re- sembles Buxus sempervirenS) and has been named Buxus macowani.

The Spectroscope and the Elements.

Professor Balfour Stewart, from an exami- nation of the evidence afforded by the spec- troscope as to the nature of the elements, concludes that it is, on the whole, in favor of their being in reality compound struct- ures, the components of which possess at- tractions for each other vastly greater than those exhibited in ordinary chemical com- binations. The fact that in the hottest stars we have the fewest atomic structures is also in favor of this hypothesis. Sum- ming up the evidence derived from both terrestrial and celestial sources we have, first, experimental evidence of various kinds, tending to show that the so-called elements are not essentially different from other bodies ; second, in the terrestrial spec- trum of pure metals at a high temperature, certain lines are obtained for some one element that are extremely near, if not coincident, in spectral position with those obtained for some other element or elements: these have been called basic lines; third, we know that in the sun's atmosphere there is a process at work tending to separate the various molecular and atomic structures, and we find that the greater number of the lines given out from the sun's hotter regions are basic lines, such as are above defined; fourth, in the very hottest stars, where the dissociation is greatest, we have only a few prominent lines given out, these being lines belonging to hydrogen, calcium, and magnesium. "I think," Professor Stewart adds, "we must conclude that the hypothesis that the elements are in reality compound bodies offers, with our present knowledge, a very good and simple explanation of the results of spectroscopic analysis in the earth, the sun, and the stars."