Popular Science Monthly/Volume 8/November 1875/Miscellany

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MISCELLANY.

We present below brief abstracts of some of the more interesting papers read at the last meeting of the British Association of the Advancement of Science. Others will follow in succeeding numbers.

 

Ice-Action.—The subject of ice-action was considered in a paper read by D. Mackintosh, F.G.S. He first discussed the question whether the so-called continental ice of Greenland was a true ice-sheet formed independently of mountains, or merely the result of a confluent system of glaciers. He then considered the state of the surface of the Greenland ice-sheet, and believed that the amount of moraine matter was locally limited and of small extent. He defended the idea of the internal purity of existing ice-sheets, and gave reasons for doubting whether glaciers are capable of persistently pushing forward the large stones they may find in their beds, though he admitted that the base of glaciers is charged with finer débris, by means of which they grind and striate rock-surfaces. He mentioned that in the lake district of England he had never seen a sharply-bordered groove on a glaciated rock-surface which might not have been produced by a stone smaller than a walnut.

He saw no reason for doubting that revolving icebergs were capable of scooping out hollows in the rocky bottom of the sea, and thought that lake-basins on the rocky summits of hills or on water-sheds might have been produced in this way. He then gave reasons for supposing that the drift-knolls called eskers, where their forms were very abrupt, might have been partly formed by eddying currents with waves generated or intensified by ice-movements, which sometimes would set the sea in motion as much as sixteen miles off.

According to Mr. Mackintosh, floating coast-ice is the principal transporter and glaciator of stones, and the uniformly striated stones found in the bowlder-clay were both glaciated and transported by coast-ice. He entered minutely into a consideration of how stones, previously more or less rounded, became flattened and uniformly grooved on one, two, or more sides, the grooves on the various sides differing in their directions. He believed that many of the stones found in the bowlder-clay of Cheshire must have been frequently dropped and again picked up by coast-ice during the passage from their original positions.

 

Ancestors of the British.—Another paper by the same author was devoted to the discussion of certain ethnological questions connected with the history of the people of Britain. He believed that the inhabitants of different parts of England and Wales differed so much in their physical and mental characteristics that many tribes must have retained their peculiarities since their colonization of the country, by remaining in certain localities with little mutual interblending, or through the process of amalgamation failing to obliterate the more hardened characteristics. The first type noticed was the Gaelic. In Cæsar's time, probably the great mass of the people of Gaul were comparatively dark in complexion and small in stature; and the race characterized by Cæsar as of tall stature, reddish hair, and blue eyes, were most likely German colonists of Gaul. There still exists in England, Wales, and Ireland, a distinct race, possessed of some of the mental characteristics anciently attributed to the Gaels. In mental character the Gaels are excitable, and alternately lively and melancholy. The Gael is also by temperament an excellent soldier, but he needs to be commanded by a race possessed of moral determination, tempered by judgment and foresight. Another characteristic of the Gaelic race is sociability.

In North Wales there are several distinct ethnological types, but by far the most prevalent is the type to which the term Cymrian may be applied. The Cymri appear to have entered Wales from the north. They are an industrious race, living on scanty fare without murmuring. Mr. Mackintosh gave a minute description of the physical and mental peculiarities of Saxons, and showed the difference between Saxons and Danes. With Worsaae, he believes that the Danes have impressed their character on the inhabitants of the northeastern half of England. He endeavored to show that between the northeast and southwest the difference in the character of the people is so great as to give a semi-nationality to each division. Restless activity, ambition, and commercial speculation, predominate in the northeast; contentment and leisure of reflection in the southwest. He concluded by a reference to the derivation of the settlers of New England from the southwest, mentioning the fact that, while a large proportion of New England surnames are still found in Devon and Dorset, there is a small village, called Boston, near Totnes, and in its immediate neighborhood a place called Bunker Hill.

 

Changes in the Courses of Rivers.—Major Herbert Wood spoke on the cause of the change of direction in the lower course of the river Oxus, by which its mouth had been diverted from the Caspian to the Aral. In the opinion of Major Wood this change is to be attributed to the abstraction of the water of the river for the purposes of irrigation, which has been practised from time immemorial. The quantity of water thus diverted has never been calculated, but, from data obtained by Major Wood during the Russian Expedition, he concludes that, between June 23 and September 10, 1874, an average of 62,350 cubic feet per second was absorbed by the irrigation canals of Khiva, an amount equal to nearly one-half the total volume of the Oxus. At the time when the river emptied itself into the Caspian the conditions of its régime were such that the volume and velocity of its summer or flood water were sufficient to clear away annually from its bed the deposits of mud resulting from the smaller volume of its winter course. From certain data it is concluded that the difference of the delivery of water between winter and summer is as one to three: thus the bed would not undergo any deterioration, its course would remain unchanged, and the river would continue to discharge itself into the Caspian. But, as soon as the volume and velocity of its summer waters were diminished by the action of irrigation canals, those compensatory arrangements of Nature would be upset, and a proportion of the muddy deposits of winter would escape the annual scouring. In course of time bars would form in the bed of the river, and in the end prevent it extending its course to the Caspian. That the Oxus has changed its lower course is proved by numerous historical documents.

 

Antiquity of the Divining-Rod.—A paper on "Rabdomancy" (or the use of the "divining-rod") and "Belomancy" (or divination by means of arrows) was read by Miss A. W. Buckland. According to the author, the staff as a sceptre was probably a later form of the horn which was thus used in prehistoric times, and in that character adorned the heads of gods. From this use of rods or horns arose a veneration for them as possessing the power of healing. Hence their use by magicians, whose chief instruments have always been a ring and a staff. These symbols conjoined are found in Egyptian, Assyrian, and Peruvian sculptures, and may be traced in some of the stone circles of Britain and in the shape of ancient Irish brooches. Belomancy, or divination by marked arrows, said to be of Scythian origin, was practised in Babylon, Judea, and Arabia, and traces of it may still be found in the popular tales of Russia and Siberia. "That the arts of magic and divination are a remnant of pre-Aryan religion is proved," said the author, "by their present existence among aboriginal non-Aryan races; and they might even be used as a test of race, so that those who in the counties of Somerset and Cornwall claim the power of divination by the rod might possibly have some remote affinity with the aboriginal inhabitants of Britain."

 

 

The Clinical Thermoscope.—Dr. Seguin, of this city, has devised an ingenious little instrument, called the clinical Thermoscope, to be used as an aid in diagnosis. It is employed for detecting the variations of temperature on the surface of the body, and estimating the rate of radiation going on therefrom.


PSM V08 D133 The clinical thermoscope.jpg

In the words of the inventor, it is "intended as a quicker and more delicate test of differential temperatures than the thermometer; and less to give the degree of heat than the velocity of its radiation." We present a cut of the instrument half the actual size. It consists of a glass tube seven inches long, with a minute bore open at one end, and terminating at the other in a bulb. An adjustable scale is attached to the outside of the tube. To prepare it for use, immerse the bulb in hot water, which rarefies the air inside. The open end is then plunged into cold water and quickly withdrawn, when a drop or two will be found to have entered the tube. This forms a "water-index," which should become stationary within an inch or two of the bulb. If it falls into the bulb, or does not approach it sufficiently, too much or too little heat was applied in the first instance, and it will be necessary to jar the water from the tube and try again. When the index is provided, adjust the scale, bringing its lowest figure on a level with the top of the column of water in the tube, and it is then ready for use. It may be applied to any part of the surface, where disturbance of temperature is suspected, but its habitual place in the hands of Dr. Seguin is, not the axilla, but the shut hand. The claims for it are, that it gives by contact indications of the volume of heat escaping by radiation, and the velocity of loss; also, that by blowing on the bulb the degree of combustion that takes place in the lungs is shown. It is likewise serviceable as a means of detecting the exact position of deep-seated local trouble, giving valuable indications where the thermometer fails.

 

A New Fossil Crustacean.—A new crustacean species, allied to Eurypterus and Pterogotus, has been described by A. R. Grote and W. H. Pitt, under the name of Eusarcus scorpionis. The specimen was found in the water-lime group at Buffalo, N. Y. Its length is 250 millimetres, and its greatest width 110 millimetres. The cephalo-thoracic portion appears to be separate from the body; the legs are in the same number as in Eurypterus; the swimming-feet appear to differ by the straighter, less rounded outer margins; the spines of the anterior feet appear to be long, curved, and to have an anterior direction. The absence of chelate appendages to the posterior margin of the feet is particularly noticeable. The first seven broad segments of the abdomen form a large ellipse. There is an evident and remarkable narrowing of the succeeding caudal segments. The interest which attaches to this remarkable crustacean arises from the discovery of a form which may be allowed to be higher than Eurypterus and Pterogotus.

 

Reptilian Affinities of Birds.—Prof. E. S. Morse has for a long time made a study of the bones of embryo birds. At this year's meeting of the American Association he recalled briefly the evidence he had shown last year regarding the existence of the intermedium in birds, by citing the embryo tern, in which he had distinctly found it. This year he had made a visit to Grand Menan, expressly to study the embryology of the lower birds, and was fortunate in finding the occurrence of this bone in the petrel, sea-pigeon, and eider-duck. This additional evidence showed beyond question the existence of four tarsal bones in birds as well as four carpal ones. In these investigations he had also discovered embryo claws on two of the fingers of the wing—the index and middle finger. Heretofore in the adult bird a single claw only had occurred in a few species, such as the Syrian blackbird, spur-winged goose, knob-winged dove, jacana, mound-bird, and a few others; and in these cases it occurred either on the index or middle finger, or on the radial side of the metacarpus. All these facts lent additional proofs of the reptilian affinities of birds.

 

American Pedigree of the Camel.—Though the evolutional pedigree of the horse may be distinctly traced in the succession of equine genera whose remains are found in the Tertiary strata of our Western Territories, nevertheless, the horse, as he at present exists, is not indigenous to this continent, but has been imported from Europe. The pedigree of the camel may also be constructed from materials supplied by American paleontology. Prof. Cope has recently unearthed a number of genera which must be regarded as the ancestors of the camel. And it is worthy of note that, although the more prominent genera of the series which resulted in the horse, for instance Anchitherium and Hippotherium, have been found in European formations, no well-determined form of the ancestral series of the camel has up to the present time been found in any formation of the Palæarctic region. "Until such are discovered," says Prof. Cope, "there will be much ground for supposing that the camels of the Old World were derived from American ancestors."

 

Arctic Meteorology.—During Weyprecht and Payer's expedition to the north-polar regions the air in winter seemed always to contain particles of ice. This was seen not only by parhelia and paraselenæ when the sky was clear, but also in astronomical observations. The images of celestial objects were hardly ever as clear and well defined as at lower latitudes, although the actual moisture in the atmosphere was far less than is usual in temperate climes. It happened very often that, with a perfectly clear sky, needles of ice were deposited in great quantities upon all objects. It was impossible to determine the quantity of atmospheric deposits, as during the snow-storms no distinction could be made between the snow actually falling and that raised from the ground by the storm. It was remarkable, however, that during the first winter the quantity of snow was small compared with that of the second winter, when the snow almost completely buried the ship. The same proportion was repeated in the quantity of rain during the first and second summer; in the first only a little rain fell and that late in the year, while in July, 1874, it rained in torrents for days.

 

Life in Elevated Areas.—The general belief in the invigorating effect of mountain-air is not absolutely justified by facts: at least there are some elevated regions the inhabitants of which show none of the vigor and élan which we should expect to find, were the common opinion correct. Dr. Jourdanet, of Paris, writes of the inhabitants of the table-land of Anahuac, Mexico, that they appear quite languid, with pale complexion, ill-developed muscles, and feeble circulation. The mortality of infants is 30 per cent. in the first year after birth. Dr. Jourdanet is satisfied that, while the proportion of red corpuscles in the blood is normal, there is a diminution of oxygen, the result of insufficient condensation of that gas under the slight pressure of the air. For this condition of the blood he proposes the name of anoxyhæmia. In Mexico, at the height of about 2,300 metres (7,500 feet) above the sea, the debilitating effects of the rarefied air are manifest. This is noticeable in brutes as well as in men. Again, the annual growth of population is scarcely ever more than three per 1,000 on the uplands, while nearer the sea-level it is six or seven. Dr. Jourdanet asserts his belief that, in countries where cold is not of itself an obstacle to life, rarefaction of the air will prevent the founding of durable states at a level higher than 4,000 metres.

 

Chinese Wheelbarrows.—In commenting on an improved style of wheelbarrow, a correspondent of the Gardener's Chronicle praises the Chinese for the ingenuity they display in diminishing to the last degree the labor of the man who propels the barrow. The Chinese barrow has but one wheel, but it is large, and placed in the centre of the bed of the vehicle; the entire load rests on this central wheel. In Shanghai, thousands of these vehicles ply for hire in the streets, the usual load being two persons, who sit on a wooden platform on each side of the wheel, resting one arm on a framework which rises above the top of the wheel, and planting one foot in a stirrup made of rope. "It is by no means uncommon, however," he adds, "to see as many as four persons conveyed without any particular effort (the ground being level) by a stalwart coolie;" garden and farm produce is transported in the same way, and even live-stock: the Chinese farmer being too sensible to attempt to drive his pigs to market, the barrow is often seen laden with a live fat hog on each side of the wheel.

 

Cave-Habitations in Kentucky.—That some of the great caves of Kentucky were, temporarily at least, used as places of human habitation, is conclusively shown by Prof. Putnam's exploration of Salt Cave. This cave, says Prof. Putnam, approaches the Mammoth Cave in the size of its avenues and chambers. Throughout one of the principal avenues, for several miles, were to be traced the ancient fireplaces both for hearths and lights. Bundles of fagots were found in several places in the cave. But the most important discovery was made in a small chamber, about three miles from the entrance. On the dry soil of the floor were to be seen the imprints of the sandaled feet of the former race who had inhabited the cave, while a large number of cast-off sandals were found, neatly made of finely-braided and twisted rushes.

 

The Use of Bushy Tails.—It is easy to see the usefulness to the opossum, monkey, and other animals, of their prehensile tails. So, too, we can recognize the value to the horse and the ox of the switches by means of which these animals repel the attacks of insects. But there are other forms of the tail the uses of which are less evident, for instance, the bushy tail seen in the fox, dog, wolf, cat, etc. Mr. Lawson Tait holds that the use of this bushy appendage is completely analogous to that of the respirator worn by persons troubled with lung-complaints, the object being to abstract from the expired air, by means of fur in the one case, and wire gauze in the other, the heat which is being taken out with it; so that the cold air inspired shall be raised in temperature before it reaches the lungs, and thereby conduce to a conservation of the bodily heat. Some interesting considerations bear on this. Animals provided with bushy tails seem to be so as a matter of correlation of growth, their bodies being always provided with thickly-set and more or less soft fur. "I cannot," says Mr. Tait, "find an animal with a bushy tail which cannot, and does not, lie curled up when asleep. I went round the Zoölogical Gardens at Dublin on a very cold morning in February, and found the civet cat, and some other bushy-tailed animals, coiled up with their noses buried in the fur of their tails.

"In the squirrel this use of the tail is very marked, and in birds the same object is accomplished by their burying their heads in the down of the shoulders. Animals provided with bushy tails are all solitary in their method of living, so far as I can find; and, therefore, an essential for their survival is some method by which variations of temperature shall be resisted. The use of the tail for this purpose is, I think, best of all illustrated in the great ant-eater (Myrmecophaga jubata), in which the hairs of the tail reach a very great size, and cover up the animal when reposing, so that he looks like a bundle of dried grass. It may also serve as a protection by mimicry in this case. Mr. Wallace states also that this animal uses its tail as an umbrella in a shower, and that the Indians divert its attention from themselves by rustling the leaves in imitation of a falling shower, and while he is putting up his umbrella they kill him. Of the quadrumana, the marmosets afford a striking instance of a bushy tail as a probable provision for protecting these delicate creatures from depressions of the temperature."

 

Remedy for Boiler Incrustations.—"Apparatine" is the name given to a substance said to be effectual in preventing incrustation in boilers, and also useful wherever gelatine and gelatine-like substances are required, as in sizing textile fabrics. It is a colorless, transparent material, obtained by treating any amylaceous substance with a caustic alkali. It is best made, however, with potato-starch, treated with a lye of caustic potash or soda. The best method of preparing the apparatine is as follows: 16 parts of potato-starch are put into 76 parts of water, and kept in a state of suspension by stirring; then 8 parts of potash or soda-lye at 25° Baumé are added, and the whole thoroughly mixed. In a few seconds the mixture suddenly clears, forming a thick jelly, which must be beaten up vigorously. It is now a colorless, transparent substance, slightly alkaline in taste, but odorless^ and of a stringy, glue-like consistency. Exposed to the air, it dries slowly, but without decomposing; and even when heated to dryness, although it thickens and swells, it continues unchanged, as when air-dried.

To prevent incrustation, the apparatine may be placed in the boiler or added to the feed-water in the tank; but the best results have been obtained by placing it directly in the boiler. Applied to silk, woolen, and cotton goods, it gives them a smoothness hitherto unattainable. When once, applied to the goods, and become dry, it appears to be virtually insoluble. Diaphanous or coarsely-woven fabrics, when dressed with apparatine, are rendered stiff and rigid. It may be used as a thickening in calico-printing.