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Popular Science Monthly/Volume 53/July 1898/Fragments of Science

Fragments of Science.

An Episode in the Early History of Animated Photography.—The following interesting letter from Henry R. Heyl is published in the Journal of the Franklin Institute for April: "Among the earliest public exhibitions of photographs taken from living subjects in motion projected by the lantern upon a screen, was that given at an entertainment held in the Academy of Music, in Philadelphia, on the evening of February 5, 1870, and a repetition of this exhibition was made before the Franklin Institute at its nest following monthly meeting, on March 16th, by the writer. The printed programme of this event contains the following allusion to this feature of the entertainment: 'The Phasmatrope. This is a recent scientific invention, designed to give various objects and figures upon the screen the most . . . lifelike movements. The effects are similar to those produced in the familiar toy called the zoetrope, where men are seen walking, running, and performing various feats in the most perfect imitation of real life. This instrument is destined to become a most invaluable auxiliary to the appliances for illustration, and we have the pleasure of having the first opportunity of presenting its merits to our audience.' The subjects exhibited embraced waltzing figures and acrobats, shown upon the screen in life size, while the photographic images were only three fourths of an inch in height. At that day flexible films were not known in photography, nor had the art of rapid-succession picture-making been developed; therefore, it was necessary to limit the views of subjects to those that could be taken by time exposures upon wet plates, which photos were afterward reproduced as positives on very thin glass plates, in order that they might be light in weight. The waltzing figures, taken in six positions, corresponding to the six steps to complete a turn, were duplicated as often as necessary to fill the eighteen picture spaces of the instrument which was used in connection with the lantern to project the images upon the screen. The piece of mechanism, then named the 'phasmatrope,' consisted of a skeleton wheel having nine radial divisions, into which could be inserted the picture holders, each consisting of a card upon which was mounted two of the photo positives, in such relative position that, as the wheel was intermittently revolved, each picture would register exactly with the position just left by the preceding one. The intermittent movement of the wheel was controlled by a ratchet and pawl mechanism operated by a reciprocating bar moved up and down by the hand. It will be apparent that the figures could be moved in rapid succession or quite slowly, or the wheel could be stopped at any point to complete the evolution. In the exhibitions at the Academy of Music, above alluded to, the movement of the figures was made to correspond to the time of the waltz played by an orchestra, and when the acrobat performers were shown a more rapid motion was given, and a full stop made when a somersault was completed. A shutter was then a necessary part of the apparatus to cut off the light rays during the time the pictures were changing places. This was accomplished by a vibrating shutter placed back of the picture wheel, that was operated by the same draw-bar that moved the wheel, only the shutter movement was so timed that it moved first and covered the picture before the latter moved, and completed the movement after the next picture was in place. This movement reduced to a great extent the flickering, and gave very natural and lifelike representation of the moving figures."


The American Professor.—Prof. Joseph Jastrow looks upon the American college professor as constituting a type of which it would be hard to find a counterpart anywhere else. His situation has recently been fully discussed in one of the magazines, and Professor Jastrow, commenting on the views there expressed, asks if the environment of our professor gives to his services a maximum of intellectual and moral value, and if it tends to develop most easily and successfully his own resources, and to urge him to the fulfillment of that function in the community for which his talents and training qualify him. The author can not answer these questions in the affirmative. There are undesirable factors in the professor's environment "which obstruct his public usefulness equally with his private happiness." He is "the type of the great underpaid, and this lack of income is, for many reasons, to be regarded as a calamity. . . . It is quite true that it were a pity that in the colleges of all places high thinking and plain living should be quite divorced; but it is a greater pity that the living should perforce be so arduous as severely to tax the energies that make for high thinking." From an investigation of the financial status of the professor, Professor Harper has found that he is on a par as to that with conductors, foremen of works, etc., with an average income of about sixteen hundred dollars, and that as a mere matter of justice his salary should be raised by one half—a conservative estimate. The average American professor suffers as much from the want of proper leisure as from the lack of a proper income, and the evil effects of the two are similar in kind; for the necessity of supplementing his inadequate salary will often direct his efforts into channels that promise some prompt remunerative rewards, rather than in the direction of the development of his maximum efficiency as a member of the university and as a personal influence. "Investigation and research, originality and scholarship come only as the slowly ripened fruits of leisure."


Montana Sapphires.—The existence of sapphires in Montana has been known for several years, but first attracted serious attention about 1891, when companies were formed and claims were taken up and examined with a view to mining fur them. The sapphire region, according to Mr. George F. Kunz, extends for about six miles along the Missouri River, the central point being Spokane Bar, twelve miles east of Helena. Another region is between seventy-five and a hundred miles east of this, centering at Yogo Gulch. Mr. Kunz describes marked differences as existing between the sapphires from these two regions. All are of the same size, but they differ in crystallization, the Missouri River gems being prismatic, and those of Yogo Gulch largely rhombohedral. The value of these sapphires in jewelry can hardly yet be estimated. "Much beautiful material has already been obtained, but little of high value. Those from the Missouri bars had a wide range of color—light blue, bluegreen, green, and pink—of great delicacy and brilliancy, but not the deep shades of blue and red that are in demand for jewelry. As semi-precious or 'fancy' stones they have value, however. The Yogo Gulch Judith River region is more promising, the colors varying from light blue to quite dark blue, including some of the 'cornflower' tint so much prized m the sapphires of Ceylon. Others incline to amethystine and ruby shades. Some of them are 'peacock-blue' and some dichroic, showing a deeper tint in one direction than in another; and some of the 'cornflower' gems are equal to any of the Ceylonese, which they strongly resemble."


The Filtration of Milk.—The wide area over which milk is collected for supplying a large city renders it practically impossible to regulate the supply in a hygienic way by control of its sources. For this reason some general method of purification, which can be applied to the milk in bulk after it has been collected, becomes an essential to a safe product for general consumption. The ordinary tests, while fairly accurate in determining adulteration, are of no value in indicating the presence of disease germs or ordinary dirt. In fact, nearly any sample taken from the milk wagons of a city will be found to contain a number of bacilli which would immediately condemn any water as unfit for drinking. Sand filtration has been practiced for several years in some Continental cities, and apparently with very satisfactory results. The filters used by Messrs. Boll, large milk dealers of Berlin, consist of cylindrical vessels divided by horizontal perforated diaphragms into five superposed compartments, of which the middle three are filled with fine, clean sand, sifted into three sizes, the coarsest being put into the lowest and the finest into the uppermost of the three chambers. The milk enters the lowest compartment, and, having traversed the layers of sand from below upward, is carried by an overflow to a cooler fed with ice water, whence it passes into a cistern, from which it is drawn direct into the locked cans for distribution. The filtered milk is not only freed from dirt, but the number of bacteria is reduced to about one third, without sterilizing. The loss of fat is, in new milk, stated to be small, but the quantity of mucus and slimy matter retained in the sand—which is, of course, renewed every time—is surprising.


Spirit Drinking and Mental Depression.—Facts brought out by Mr. Bateman, of the British Board of Trade, in reference to the amount of drinking in different countries make the people of the United Kingdom more moderate in their drinking habits than has generally been supposed, and place them among the more temperate nations; for while in the consumption of beer, SO.T gallons a head, they exceed the Germans as a whole with 25.5 gallons a head, the relatively small quantity of wine drunk, less than half a gallon per head, as against 29.50 gallons in France and the adjoining countries, more than restores the balance. And this result is not changed when the stronger drinks than wine are taken into consideration—1.9 i gallons per head in Germany, 1.85 in France, and 1.01 in the United Kingdom. The Bavarians are the greatest beer drinkers, consuming an average of fifty gallons each in a year; next to them are the Belgians, with 43 gallons. The United States appears in the table as a vastly more temperate nation than any of these, its average rate of consumption of beer, wine, and spirits being less than half that of Great Britain. The London Spectator, taking Mr. Bateman's tables as its text, tries to find a mental rather than a physical cause for the appetite for drinking, and discovers it in the use of spirits as a means of obtaining relief from depression. In the United States, where the climate is exhilarating, life is easy, and the people are satisfied, drinking is decreasing; while "it is in France that drinking is now most prevalent, and is assuming the form least connected with the actual enjoyment of fermented liquor." Though wine is plenty and all are trained from childhood to drink it, the people "are taking to strong spirits of peculiarly nasty flavors," and some are spending nearly half their wages upon them. This, it thinks, is because "in France more than in any other country the people are becoming depressed and pessimistic, partly through the general loss of their faith, partly through a consciousness that they are not as great in the world as they think they ought to be, partly through the rise of the savage pecuniary discontents which produce what we are accustomed to call socialism."


Insects, and Books about them.—In a Brief Historical Survey of the Science of Entomology, by C. L. Marlatt, president of the Entomological Society of Washington, an estimate is made of the extent of entomological literature. Hajen's Bibliotheca, in 1862, listed 4,766 authors, 18,130 distinct titles, and 851 anonymous publications. The last volume of the Zoological Record, for 1895, gives 1,251 titles of publications on insects, which might perhaps be equivalent to seventy-five 500-page volumes; and Mr. Marlatt supposes, as a very conservative estimate, that what would amount to 2,000 such volumes have been published since the date of Hajen's work. In economic entomology, Henshaw's Bibliography of 1888 contains 5,424 titles and the names of more than 500 writers; and about 700 entomological papers have appeared since then from the agricultural experiment stations. Hence, the author estimates the bulk of writings on insects available now at between 12,000 and 15,000 volumes; and this does not include the recent literature of apiculture. On a similar basis of calculation it is estimated that there are between twelve and fifteen hundred people now living whose works on insects are of such a character as to be noticed in the standard annual books of record. Besides these are the writers on bees, and the very large number of collectors of insects who rarely write on the subject. The number of species of described insects, excluding arachnids and myriapods, is estimated at 250,000; and it may be that, the world over, there are 10,000,000 species in all. Thus only one in forty of probably existing species is known—a fact that seems to throw grave doubt on much of our classification and characterization of genera. About 1,200 new genera and subgenera are added every year. "That the entomologists of the world have ample material with which to work, and that there is no alarming prospect in the immediate future of exhaustion of the field, is strikingly apparent." Dr. David Sharp has recently computed that in the matter of bulk insects probably outrank all other animals together, their small size being more than counterbalanced by the vast number of species and enormous multitude of individuals.


Economical Uses of Bacteria.—Prof. H. Marshall Ward, in his presidential address, which was read in his absence before the Botanical Section of the British Association, dwelt at considerable length on the many industrial processes which depend more or less for their success on bacterial fermentations. The subject is young, he says, but the little that has been discovered makes it imperative that we should go on, for the results are of immense importance to science, and open up vistas of practical application which are already taken advantage of in commerce. A bacillus has been discovered by Alvarez which converts a sterilized decoction of indigo plant into indigo sugar and indigo white, the latter then oxidizing to form the valuable blue dye, whereas the sterile decoction itself, even in the presence of oxygen, forms no indigo. Certain stages in the preparation of tobacco leaves and of tea depend on a carefully regulated fermentation, which must be stopped at the right moment, or the product is impaired or even ruined. While in flax and hemp the best fibers are separated by steeping in water till the middle lamella is destroyed, not every water is suitable for the process, but only that containing a particular bacillus, which destroys the pectin compounds of the lamella and leaves the cellulose. A process depending on this fact has been patented in the United States. The steeping of skins in water preparatory to tanning involves bacterial action for removal of the hair and epidermal coverings; and the swelling of the limed skins is a fermentation process. Hay and ensilage have to go through fermentations involving bacterial action. The various flavors of butter and cheese are each produced by special bacteria, and the cultivation of them has become a considerable business, so that the production of whatever flavor may be desired has become a matter of reasonable certainty.


Areca and its Properties.—The areca nut, a favorite stimulant of the many millions of people living in the East Indies and beyond, is the fruit of a tree, the Areca catechu, which, as described by M. Ernest Martin, following Chinese authors, has a trunk like that of the bamboo, straight and without branches, jointed in the upper part, with leaves like those of millet or sugar cane, under which are spathes containing fruits about as large as plums and protected by thorns. These nuts are edible. The bark of the tree is like that of the Paulownia; and it is on the whole very like the cocoa palm. It is regarded as one of the handsomest ornaments of the woods of the southern part of the extreme East. The nut is extensively used as a stimulant and as a remedy. It forms the basis of a preparation, with betel and lime, which is made to be chewed. After it has been used for a little while the teeth begin to assume a dark yellow or even blackish hue, from which the Chinese say that the Cochin-Chinese, Annamites, Cambodians, etc., tattoo their teeth. The effect sought in chewing areca is an excitation which, affecting the salivary glands first, extends from them through the whole organism. When the indulgence passes beyond the bounds of "moderation," disorders set in, which first affect the teeth; and even young Annamites are not infrequently found toothless in consequence of excess. Medical properties are claimed for the areca by the Chinese doctors. It is said to help digestion, to drive away the deleterious miasms that ferment in the body, to be an efficient vermifuge, to prevent flatulence, to heal ulcers, and to be a prophylactic against malarial influences. The people of marshy regions use it instead of tea, on account of its properties as a febrifuge. When taken in strong doses, it produces intoxication. A Chinese poet. Sou Tong, who lived in the eleventh century, celebrates this property in his verses, but adds that when one is drunken with wine he has only to chew areca to be relieved of his heaviness and brightened up. The nut has the other properties of assuaging hunger, of being an excellent eupeptic, of drying up suppurations, for which the Annamite doctors use it powdered, and above all as a remedy for worms, particularly the tapeworms; and it has other uses in Indo-Chinese medicine.


Trees in Tennessee.—But few States in North America can show a greater variety of valuable timber trees than Tennessee. Almost every tree to be found in the United States grows in that Commonwealth. The fact is ascribed by Colonel J. W. Killibrew, in a paper he read before the American Forestry Association, partly to the great diversity of soils, partly to the great differences in elevation and consequently of climate, and partly to the abundant rainfall. Colonel Killibrew has collected a hundred and thirty kinds of wood, eight or ten of which are, however, exotics. Among the indigenous trees are four varieties of ash, three of birch, two of beech, two of magnolia, five of elm, two of fir, four of gum, eight of hickory, four of locust, three of mulberry, three of maple, four of poplar, six of pine, three of sycamore, fourteen of oak, three of willow, and two of walnut, besides many single valuable kinds, such as red cedar, chestnut, cypress, Cottonwood, pecan, linden, spruce, dogwood, tiswood, etc. Nearly all the western counties of the State were originally covered with heavy forests, in which many species are nearly evenly distributed. The tulip tree, the white oak, red oak, hickory, gum, black walnut, wild cherry, basswood, ash, elm, and beech are interspersed with one another, while cypress abounds in the swamps. In Middle Tennessee, the supply of good timber is very scarce in the richer agricultural districts; but in a few counties in the southwestern part of this district is a large area of virgin forest. The most valuable timber trees in East Tennessee are the tulip, pine, chestnut, and white oak. The timbered tracts throughout the State consist largely of woodlands attached to farms. In some parts of East Tennessee there are, according to Mr. George H. Sudworth, dendrologist, hundreds and in other parts thousands of acres of standing white pine which would yield very large amounts of timber. The bulk of it lies in the northern half of East Tennessee, but it extends in a more or less scattered growth clear down to the southeastern corner of the State. Much of it is old, and in some localities it has ceased to grow. The bulk of this pine occurs alike in the narrow valleys and on the long, steep, sharp mountainlike ridges. The destruction of the forests is growing with alarming rapidity. The State, however, still has a large supply of timber; and in the future forestry of East Tennessee the regeneration of the white pine must be an important feature. Fortunately, the conditions are such as to make it comparatively easy.


North American Grasshoppers.—The common short-horned grasshoppers oae sees every summer day—constituting a group which is described as forming the prevailing type of orthopteran life throughout North America—is the subject of an elaborate essay by S. H. Scudder which is printed in the papers of the United States National Museum (Revision of the Orthopteran Group Melanopli (Acrididæ)). These active insects, whose gymnastic feats cheer and enliven our summer walks through fragrant meadows, are of considerable economical importance, as may be realized when we recollect the destruction inflicted several years ago by the Rocky Mountain locusts, and the careful investigations and elaborate reports of which they were the subject. This voracious acridian, Mr. Scudder says, has numerous closely related allies in all parts of the United States, many of which often abound to such an extent as to do serious damage to crops, and a few of them have been known to migrate in a similar fashion to the Rocky Mountain species. The Melanopli are almost exclusively an American group. A single genus is represented in the Old World, north of 35° north latitude. With that exception, almost all the genera and species of grasshopper are in North America; although four genera, not described by Mr. Scudder, with twenty-four species, are found in South America. Eleven of the North American genera, with nineteen species, live exclusively in Central America and Mexico, passing the border of the United States only narrowly, and these countries also make two South American species at home. Six genera range over twenty degrees of latitude; two are known only in Florida. Most of the genera are Western; four are peculiar to the Mississippi Valley; three are found on opposite sides of the continent, and are therefore presumed to range over the whole of it; five are characteristic of the extreme West; and four are confined, or nearly so, to the region north of latitude 35°. For the purpose of his essay, Mr. Scudder examined nearly eight thousand specimens, of which about seven thousand belonged to the single genus Melanoplus.


The Invention of Printing.—From a recent number of The Chap Book we learn that the much-discussed question of who invented printing has been recently reopened by Gilliodts-van-severén, curator of the Archives of Bruges, who claims that a Jean Brito, of Bruges, printed from movable types before Gutenberg or Coster. The volume on which this claim is based, which is now in the Bibliothèque National at Paris, is an edition of the Doctrinal of Jean Gerson, the celebrated chancellor of the University of Paris, who died in 1429. There is no date on the volume, but on the last page are some Latin verses, the literal translation of which is something as follows: "Notice the beauty of this present writing; compare this work with other works; put this book by the side of another book; see with what neatness, with what care, with what elegance, this impression is made by Jean Brito, bourgeois of Bruges, who discovered without teaching from any one his marvelous art, and as well his astonishing implements, no less worthy of admiration." In 1773 the Abbé Ghesquière called attention to these verses, but the two schools of Mayence and Haarlem, which had narrowed the controversy down to Gutenberg and Coster, refused to admit a third competitor. M. Gilliodts-van-severén, who has reopened the controversy, has written a large volume on Brito. He has discovered many new documents in support of the latter's rights and much interesting matter concerning his life.


Women opposed to Woman Suffrage.—The energetic pressure of the agitation in favor of woman suffrage has met its natural reaction in the organization of women opposed to having the duty of voting thrust upon them. An association of this kind was formed in Massachusetts about fifteen years ago and had the satisfaction of seeing a woman-suffrage measure defeated by popular vote in 1895. The New York State Association opposed to the Extension of Suffrage to Women was formed in April, 1896, and now has a standing committee of more than one hundred women, twenty thousand members, and branches in some of the large cities. The Illinois association, formed in May, 1897, has issued a circular defining the position and motives of the women who have taken this stand, and answering some of the arguments that have been put forward in favor of woman suffrage. Exclusion from the franchise, the circular says, does not imply inferiority, but division of qualities. "A little reflection shows that the kind of intelligence which the lawmaker should possess, the knowledge of the practical things of the outside world, such as currency, banking, the franchises granted to corporations, the general control of vast commercial and manufacturing interests, with other details of practical life, not easily enumerated, are affairs which lie almost wholly within the domain of man, and which it would be a sad waste of energy for women in general to become familiarly acquainted with. . . . Does it therefore follow that women are on the whole inferior to men? By no means. In her own domain, which includes the most vital, the most spiritual, the most progressive elements of life, woman is as much man's superior as he is hers in outer and material things." Everywhere, the circular continues, intelligent women of good character are effective agents in good work, public as well as private. It is only the women who are without moral influence who lack this power; and to give them the ballot would not only be a mistake in itself, it would place in their hands the power utterly to nullify the moral influence of the more enlightened of their sex. The pure and educated women of the nation, non-voting, and thus unbiased by the selfish considerations which naturally sway political aspirants, should form the strong. est and purest element of conservatism possible." The noblest and most useful work of woman has ever been and ever will be "in that domain in which man can never take her place, or become her peer or rival. . . . We believe that men do look to women, and it is our desire and prayer that they may never look in vain, for the maintenance of the home, the upholding of lofty, pure ideals of domestic and social life, the moral education and training of children. . . . It is the compensation which woman owes to the state for the protection which she enjoys in the home, and for immunity from public labor and service, that she should rear her children with right habits and instill into their minds true principles and noble ideals of life, and she can not do this while she is managing political machines and besieging legislatures."