Popular Science Monthly/Volume 52/January 1898/Fragments of Science

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Fragments of Science.

Chinese White Wax: a Curious Industry.—George F. Smithers, consul at Chung-king, China, is authority for the following: In the Chien-ch'ang Valley, and especially in the neighborhood of Chung-king, which is the chief wax-producing country, perhaps the most prominent tree is the Ligustrum lucidum, or "insect tree." It is an evergreen, with dark-green, glossy, ovate leaves springing in pairs from the branches. On these trees, attached to the bark, are numerous brown, pea-shaped excrescences. The larger of these scales are readily detachable, and when opened present either a whitish-brown pulpy mass, or a crowd of minute animals looking like a mass of flour. Upon close examination these masses are found to consist of a swarm of brown or dirty-white creatures, each provided with six legs and a pair of antennae. This is the white wax insect, the Coccus pe-la of Westwood. Many of the scales also contain either a small white bag or cocoon covering a pupa, or a perfect imago in the shape of a small black beetle. This beetle is a species of Brachytarsus. If left undisturbed in the broken scale, the beetle, which from his ungainly appearance is called by the Chinese nin-êrh (buffalo), will continue to burrow in the inner lining of the scale, which is apparently his food. The Chinese declare that the beetle eats his minute companions in the scale. When a scale is plucked from a tree, an orifice where it was attached to the bark is disclosed. By this orifice the cocci are enabled to escape from the detached scales. Two hundred miles to the northeast of Chien-ch'ang, and separated from it by a series of mountain ranges, is the prefecture of Chia-ting, within which insect white wax as an article of commerce is produced. At the end of April the scales are gathered from the trees, made up into paper packets, each weighing about sixteen ounces, and transported by porters across the mountains to Chia-ting. Great care has to be taken in the transit of the scales. The porters travel only during the night, as the high temperature during the day would cause a too rapid development of the insects and their escape from the scales. Notwithstanding the greatest precautions, however, each packet loses about an ounce in transit. West from the right bank of the Min River, on which the city of Chia-ting lies, stretches a plain to the foot of the sacred O-mei range of mountains. This plain is an immense rice field, being well watered by streams from the western mountains. Almost every plot of ground here, as well as the bases of the mountains, are thickly edged with stumps, varying from two or four to a dozen feet in height, with numerous sprouts rising from their gnarled heads. These stumps resemble at a distance our own pollard willows. The leaves spring in pairs from the branches; they are light green, ovate, serrated, and deciduous. It is probably the Fraxinus chinensis, a species of ash. The tree is known to the Chinese as pai la shu (white-wax tree). On the arrival of the scales from the Chien-ch'ang Valley, they are made up into small packets of from twenty to thirty scales, each inclosed in a leaf of the wood-oil tree. The edges of the leaf are tied together with rice straw, by which also the packet is suspended close under the branches of the wax tree. A few holes are made in the leaf, so that the insects may find their way through them to the branches. On emerging from the scales the insects creep along the branches to the leaves, where they stay for a period of thirteen days. They then descend to the branches and twigs, the females probably to provide for a continuation of the race by developing scales in which to deposit their eggs, and the males to excrete the substance known as white wax. Whether or not this wax is normally intended as a protection for the scales is uncertain. The wax first appears as a white coating on the under sides of the boughs and twigs, and looks very much like sulphate of quinine. It gradually spreads over the whole branch, and attains after three months a thickness of about a quarter of an inch. The branches are then lopped off and as much of the wax as possible removed by hand. This is placed in a pot of boiling water. The wax, melting, rises to the surface, is skimmed off, and placed in a round mold, whence it emerges as the white wax of commerce. An inferior darker quality is made by boiling twigs and all together. When the branches are lopped off a wax tree, a period of three years is allowed to elapse before the tree is again used. Since the introduction of kerosene oil into China the use and hence production of this wax have much decreased, it having been largely used as an external coating for candles on account of its high melting point (160° F.).


Psychic Development of Cats and Dogs.—Prof. Wesley Mills's experiments on the psychic development of young animals continue to be very interesting. In the kitten, while the first stages are very slow and obscure, the author finds that in the progress of all the senses to full development the course, while marked by definite steps, is often so rapid that distinct advances may be marked in a single day. Apart from the senses, etc., there seems to be a definite order in which all the features of feline nature appear, as, for instance, purring, crouching, stalking, etc. Certain physical changes are correlated in time with certain psychic developments, the significance of which is in some cases clear, in others obscure. Comparing the two animals, the cat, on the whole, develops more rapidly than the dog, the greatest difference between them appearing in the social and gregarious nature of the dog and the independent and solitary traits of the cat. The dog is docile in the highest degree; the cat to a slight degree, compared with its intelligence. The play instinct is early and highly developed in both, and the peculiar qualities of each are well exhibited in the manifestation of it. In will power and ability to maintain a separate existence the cat is superior to the dog. In the higher grades of intelligence the wisest dogs are much in advance of the most knowing cats; and this is foreshadowed if not exemplified in the early months of existence. The nature of the dog as compared with the cat tends to beget prejudices in his favor with the mass of persons, so that in general the dog is overestimated and the cat underestimated with the great majority; at the same time the dog's nature is much nearer that of man than the cat's. "The kitten may amuse, but even a puppy dog touches chords of sympathy in the heart of man that the cat can never reach."


An Incandescent Oil Lamp.—Ever since the successful introduction of the incandescent mantle in gas lamps, inventors have been hard at work trying to construct an oil lamp which could be used to replace the gas in heating the mantle. Many such lamps have been contrived, but up to the present time none of them have proved satisfactory. It is now announced, however, in Industries and Iron, that such an oil lamp having an atmospheric burner has recently been offered for inspection in London, which seems to be free from most of the defects of its predecessors, and which promises to become a great commercial success. It is called the "Era" incandescent petroleum burner, and consists of a "gallery burner," spreader, mantle, and chimney—in fact, everything necessary except the oil container. The mantles are of special form, being somewhat shorter and apparently broader than those used for coal-gas burners, and the mesh of the material is more open. It is claimed that the lamp will give a fifty-candle light, with rather less than one third the oil consumption customary with a burner of the ordinary type having equal illuminating power. The air blast, which is necessary for converting the luminous flame into a heating one, is secured by the use of an unusually long chimney. The adjusting of the flame to its proper height is effected by the ordinary rack mechanism operating on the wick case and wick. If the flame is too high it begins to "sing," and this serves as a ready means for regulating it. It is stated that the complete apparatus, with spare gallery and cap, is sold retail at about $2.40, and can be fitted to any type of lamp having a fourteen-line cylindrical burner.


Chemistry of a Silk Jacket.—Dr. T. L. Phipson has recently had occasion to analyze a piece of black dress silk of medium quality, at the request of a lady who wished to ascertain its value. The results are curious. The material contained a large quantity of substance that was not silk at all, being considerably "weighted." It would not burn with flame, but smoldered away like tinder and left a large amount of ash, the principal ingredient of which was oxide of tin. The precise composition was: Water, 11·43 parts; ash (mostly oxide of tin and silica), 14·30; real silk, 28·14; organic matters, etc., not silk, 46·13; in all, 100 parts; nitrogen, 4·76 parts. Respecting the tin, the author observes that he has examined specimens of poor tin ore from Cornwall that did not contain more tin than this material for a lady's blouse; "and I at once realized the fact that the silk dresses worn by the ladies we see daily parading in Regent Street and Bond Street, taken together, would represent a Cornish mine of very fair quality." The analysis brought to light the fact that the durability of a piece of silk can be determined by this method. The probable life—that is, the length of time before it would become "utterly shabby, greasy-looking, and showing the threads"—was estimated by a milliner at about three months. It is said, however, that the public prefer the cheap products that get shabby so soon because the fashions change so rapidly that it would be useless to buy silk of better quality.


A Primitive Maya Jewsharp.—Mr. M. H. Saville gives the following interesting information in a recent note in the American Anthropologist: The ancient forms of musical instruments known to have been used in Yucatan have been almost entirely superseded by those introduced since the Spanish conquest. In some of the interior pueblos the tunkul, or ancient wooden drum, is still used on feast days. "During the winter of 1890-'91, while engaged in explorations at the cave of Loltun, we employed a number of Mayas who came from small villages in the interior remote from Spanish influences. Their evenings were passed in singing plaintive melodies in their native tongue, accompanied by a primitive form of stringed instrument which I have never seen described. It was called hool, and consisted of a piece of ropelike vine (ohil) stretched between the two ends of a pliable stick, making a bow about two feet long. One end of this bow is placed near the face, about one third of the distance from the end, so that the mouth covers but does not touch the string, forming a resonator. Between the string and bow a piece of wood is placed in such a manner that it may be pressed against the string or relaxed at will. The tones are produced by tapping on the string, and somewhat resemble those made in playing a jewsharp, but are more agreeable to the ear. Variation of tone was produced by varying the pressure of the stick upon the string and also by the opening or partial closing the mouth. The music is weird and not unpleasing."


The Jesup Expedition.—The object of the Jesup expedition to the North Pacific, as explained by Prof. F. W. Putnam in the British Association, is to study the question of the supposed Asiatic origin of the ancient American peoples. The whole cost of the expedition is to be paid by Mr. Morris K. Jesup. A thorough and careful exploration will be made of both sides of the Pacific Ocean north of the Columbia River in America and of the Amoor in Asia. Several parties will be placed in the field, each including a thoroughly qualified ethnologist, a physical anthropologist, and an archæologist, who will make comparative studies of the physical characteristics of the different peoples, their languages, their myths and traditions, their customs and arts, and will also study the archæology of the whole region. Dr. Boas has been in the field since June, 1897, in British Columbia, and has established four parties, who are working under his immediate direction. The first party will go to Asia in the spring, and other parties will be put into the field from time to time as the men are selected who are properly prepared for the work. In the discussion which followed the presentation of this account, Professor Putnam expressed his belief that there had been an American-Asiatic contact. Mr. Frank H. Cushing was of a different opinion, and thought that the resemblances between the arts and customs of aboriginal Americans and Asiatics were merely the results of similar psychic developments under corresponding environments. Professor Morse brought forward data that led him to the conclusion that not a dialect, art, tool, or weapon was found in America at the time of the discovery that had been in use in the Old World.


Object Lessons in Road Building.—The following, in a circular of information from the New York Agricultural Experiment Station at Geneva, will be of value to all interested in the good-roads problem: The attempt to stimulate and inform the public mind in the direction of good roads is being undertaken in two ways: first, by the distribution of good roads literature; and, second, by the building of sample roads in connection with State colleges and experiment stations. The first sample road to be built is already completed at New Brunswick, N. J. (this was written about the first of August), and the second one, which is being constructed in connection with the Geneva station, is now in its first stages. This sample road, which has been made possible through the generosity of private citizens and through liberal aid from the town and city of Geneva, will be over seven thousand feet long, being located in an important street which connects the experiment station with the city. A section of this, perhaps eight hundred feet, will be macadamized in the center to the width of eight feet, with rolled dirt roads on either side, this being designed as an improved country road. The remainder, something over a mile, will be macadamized in the center fourteen feet, with dirt roads on either side. It is now also proposed to lay at least two hundred feet of the steel track which is now attracting so much attention as a possible efficient and economical road in sections where stone is scarce and costly.


A Troublesome "Water Weed."—About seven years ago a few plants of the water hyacinth were accidentally thrown into the St. John's River in Florida. Since then they have increased so enormously as to prove a serious obstruction to navigation, so much so indeed that about two years ago it was found necessary to call in the aid of the War Department. Still later, in the early part of 1897, the Department of Agriculture sent one of its agents, Mr. Herbert Webber, to the region in order to investigate more fully the physiology and habits of this dangerous vegetable. His report has been recently published and is authority for the following statements: The plant grows chiefly in sluggish fresh water, the character of the water seeming to have much to do with its growth. It can not live in brackish water, and is promptly killed when it is dislodged and floats down into salt water. It is normally propagated by seeds and stolons. When the plant first appeared in the river its beautiful masses of flowers were much admired, and it was introduced at various points for its beautifying effect. At this time no one expected the plant would become a nuisance. In a very short time, however, it began to seriously interfere with navigation, and its effect on the lumber and fishing industries has been most disastrous. It is feared that its eradication is impracticable.


Unexplained Tidal Variations.—It has been demonstrated by Lord Kelvin and Professor Darwin that the tidal movement is made up of many waves, depending upon different functions of the moon and sun. Some of these movements are half daily, some daily. The tidal movement is nowhere more simple and regular, says Captain W. J. L. Wharton, than in the British Isles, in remarkable contrast to the opposite American coast, where it is very complicated. The minor tides, which in most parts of the world considerably affect the volume of the whole, are in Great Britain comparatively insignificant; why, is not yet explained. Some curious interference phenomena originating in the meeting of tidal waves from opposite directions, or in rebounds from the coasts, have been observed in the British Isles. The tidal range of about fifteen feet on the western part of the southern coast of England diminishes as we go eastward to one of six feet near Poole, then increases to Hastings, where it is twenty-four feet, and then, farther east, gradually diminishes. This is due to reflection from the French shores, which brings waves that here re-enforce, there reduce, the main wave, according to details so complex that they have not yet been studied out. Variations in the mean range of tides on many coasts may be accounted for as resulting from such reflections, which may come from longer distances and be more numerous than we are now aware of.


Toads at Dinner.—The toad does not take dead or motionless food. Only living and moving insects, centipeds, etc., are devoured, while worms or other larvæ disturbed by their hopping are safe so long as they remain curled up; but as soon as they move they are captured. The toad's tongue, its only organ for seizing food, is soft, extensile, attached in front but free behind, and is covered with a glutinous substance that adheres firmly to the food seized. So rapid is the motion of this weapon that a careful watch is necessary in order to see the animal feed. At night, soon after sunset or even before on cool evenings, the toad emerges from its shelter and slowly hops about in search of food. Something of a regular beat is covered by these animals, whose sense of locality is strong. In the country this beat includes forage along the roadside, into gardens and cultivated fields, and wherever insect food is abundant and grass or other thick herbage does not interfere with getting about. In cities and suburban villages the lawns, walks, and spots beneath the electric lamps are favorite hunting grounds. At Amherst, Mass., Mr. A. H. Kirkland, from whose paper we derive these observations, once counted eight large, well-fed toads seated under an arc light and actively engaged in devouring the insects which, deprived of wings, fell from the lamp above. At Maiden, Mass., a colony of about half a dozen toads sally forth on summer evenings from under the piazza of a citizen's house, go down the walk, cross the street, and take up their stations under the arc lamp, where they feed upon the fallen insects till the current is turned off, when they return to their accustomed shelter.


Unexplored Regions in Asia.—In the coming century there will be abundance of work for explorers in Asia, said Dr. J. Scott Keltie in the British Association, and plenty of material to occupy attention. They lie in two separate regions. In southern and central Arabia there are tracts which are entirely unexplored. These regions are probably a sandy desert. At the same time they are, in the south at least, fringed by a border of mountains, whose slopes are capable of rich cultivation, and whose summits the late Mr. Theodore Bent found to be covered with snow. If any traveler cared to face the difficulties, physical, political, and religious, which would probably be met with, he might be able to tell the world a surprising story. Another region in Asia where real pioneer work still remains to be done is Tibet and the mountainous districts bordering it on the north and east. Lines of exploration have in recent years been run across Tibet by Russian expeditions like that of Prejevalsky, by Rockhill, Prince Henry of Orleans, Bonvalot, Bower, Littledale, Wellby, and Malcolm. From the results obtained by these explorers we have formed a fair idea of this, the most extensive, the highest, and the most inhospitable plateau in the world The forbidden city of Lassa is at present the goal of several adventurers, although as a matter of fact we can not have much to learn in addition to what has been revealed in the narrative of the native Indian traveler, Chandra Das. The magnificent mountain region to the north and east of Tibet furnishes a splendid field for the enterprising explorer. Then there are the series of parallel mountain chains southeast of Tibet through which the upper waters of the great eastern Asiatic rivers run; a region in Turkestan; the Malay Peninsula; and the great islands of the Malay Archipelago and the Philippines.