Popular Science Monthly/Volume 4/November 1873/Miscellany

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MISCELLANY.

Yosemite Valley of Glacial Origin.—In the summer of 1872, Prof. Joseph Le Conte, of the University of California, with several students of the institution, visited the Yosemite and the mountains contiguous, and carefully examined the results of the glacial action which were everywhere apparent. His conclusions were stated in an able paper, published in the American Journal of Science for May. The Yosemite Valley, he thinks, was once filled to the brim with a great glacier. In this he differs from Prof. Whitney, who in his guide-book expresses the opinion that there is no evidence that such a glacier existed.

Prof. Le Conte observes that glaciated forms are unmistakably observable at many points on the walls of the valley, and in some places even to the brim. In the contour of the walls of the valley, their rounded form, where the rock is hard, standing unbroken and without débris at the base, he finds proofs of glacial erosion. On the north side of the valley, every projecting shoulder is thus rounded, and in some cases the smoothness is so complete, even at a considerable height, that the rocks glisten in the sunshine. Where the rocks are soft, and on the southern side of the valley, which is in shadow, frost and other agencies have done their work of disintegration. The surfaces are broken, and the débris lies at the base.

The bed-rock of the valley is covered with mounds of bowlders and sand, which are terminal moraines of glaciers, and by stratified lake-deposits, the lakes having been formed by the glacial mounds obstructing the flow of waters.

But it was from the higher elevations that the wonderful features of the glacial erosion were most distinctly observed. "From the edge of the rim of Little Yosemite," says the author, "we had a magnificent bird's-eye view of the wonderful domelike form of nearly all the prominent points about this valley, and their striking resemblance to glaciated forms cannot be overlooked. The whole surface of the country is moutonné on a huge scale. If so, then the greater domes about the Yosemite have been formed in a similar manner. If so, then the whole surface of this region, with its greater and smaller domes, has been moulded beneath a universal ice-sheet, which moved on with steady current, careless of domes."

This great ice-sheet preceded the separate glaciers which completed the erosion of the valleys of which Yosemite is one, and the scattered snow-fields which were discovered by Mr. Muir, of the expedition, are feeble remains of the old glaciers. In the opinion of Prof. Whitney, the Yosemite was formed by a sudden engulfment of a portion of the sierras, but Prof. Le Conte observes that Yosemite is not unique in form, and probably not in origin. There are many Yosemites. Many of the great glacial valleys become deep, narrow cañons, with precipitous walls near the junction of the granites with the slates. This is the position of Yosemite. It occurs in the valley of the American River and the valley of Hetch Hetchy, which, says the author, almost rivals the Yosemite in grandeur, and, in his opinion, all these deep, perpendicular slots have been sawed out by the action of glaciers, the verticality of the walls having been determined by the perpendicular cleavage of the rocks.

Origin of the Potato-Disease.—Messrs. T. & E. Brice, of Plymtree, England, claim to have discovered the cause of the potato and the foot and mouth diseases, which they assert to be nothing else but the employment of chemical manures. It is remarkable, say they, that both of these diseases made their appearance about the same period. It is some 250 years since the potato was introduced into Britain, and there is no record that the disease ever existed until the year 1845, when, subsequently to a continued rain for some days together, the potato was found to be diseased generally throughout the kingdom. Previous to that time the chemical manures had been introduced, and they were used in great abundance the same season that the potato-disease first appeared. Messrs. Brice were then of opinion that the manure was the cause, and, having since investigated its principles and action, they find that it contains a very active poison—sulphuric acid: "Its particles readily attract the particles of water, producing fermentation, and sometimes causing putrefaction of the compound they adhere to. If the chemical manures are distributed over the land in a dry season, and there is not enough rain to cause fermentation, the sulphuric acid remains fixed on the earth; if it is applied in a wet season, the rain causes fermentation; the effluvium ascends in the atmosphere, and, mixing with the vapors, helps to constitute clouds, when there is a return in poisoned rain and dew on the potatoes, and other bodies as well. Putrefaction of the potato is the consequence, and it has a very offensive smell." The authors have made some experiments with a mixture of water and sulphuric acid. Fermentation and poisoning of the water were the result, and an application of the mixture to the potato caused disease.

But the question naturally arises, Why should the sulphuric acid cause disease only in the potato and not in other plants? and on this point the Messrs. Brice leave us in the dark. Here we may mention another theory which has been proposed to account for this potato-blight. It has been observed that the electrical state of the atmosphere has something to do with the matter, and in Ireland the potato-crop is described as wearing a blighted appearance after a protracted thunder-storm. The theory is, that the electrical condition of the atmosphere causes the conversion of the starch into dextrine, sugar, etc., and the tuber then melts away. But again we ask, Why did not the same causes produce the same effects previous to 1845?

As regards the foot and mouth disease, the cattle and other animals travel and browse where the poison has fallen, and it is taken in with their food. The active particles adhere to their feet, lips, and mouth, destroying the scarf-skin and mucous membrane of the mouth and throat. The symptoms are such as might be produced by sulphuric and other corrosive acids.

A Substitute for Parchment.—Parchment-paper has several properties in common with animal membrane. It is obtained by the action of sulphuric acid or chloride-of-zinc solution on unsized paper. When sulphuric acid is employed, the best solution is one kilogramme (2.20485 pounds) English concentrated sulphuric acid to 125 grammes (about 4.4 ounces) of water. The paper is dipped into the acid so as to moisten both sides uniformly. The length of time it is to remain in the bath depends on its own thickness and density. The minimum time for the ordinary unsized paper of commerce is 5 seconds, the maximum 20. When the acid has acted a sufficient length of time, the paper is first dipped in cold water, then in dilute ammonia, again in water, to remove the acid, and finally it is dried. When it is left to itself to dry, it becomes shriveled, and has a bad appearance. To guard against this, the following process is adopted: An endless strip of paper is passed by machinery first through a vat of sulphuric acid, and then through water, ammonia, and water again; next a cloth-covered roller deprives it of a portion of the water, and finally it is pressed and smoothed out by means of polished heated cylinders.

When properly manufactured, parchment-paper has the same color and translucency as animal parchment, its structure having undergone a change from fibrous to corneous. In point of cohesion and hygroscopicity, it is very much like common parchment. When dipped in water, it becomes soft and flaccid. It is impermeable to liquids, except by dialysis. These qualities render parchment-paper specially suitable for diplomas, important papers, and in general for documents which it is desirable to preserve. As compared with ordinary parchment, this paper possesses the advantage that it is very little liable to be attacked by insects. Then, too, the characters inscribed on it cannot be effaced without difficulty, and, when effaced, cannot be replaced by others—a perfect guarantee against all kinds of falsification. By reason of its firmness and durability, it is specially suited for plans and drawings, particularly architectural drawings, which are much exposed to moisture. Further, it might be used for covering books; or books, maps, etc., for use in schools, could be printed on it, and would be very durable. In place of animal membrane, it is well suited for covering jars of fruit, extracts, etc., as also for connecting the parts of distilling and other apparatus. It furnishes excellent casings for sausages. In surgery it is employed instead of linen, oiled cloth, and gutta-percha, for dressing wounds.

Improvements In Street-Sprinkling.—An improved method of sprinkling streets has been patented in England, by means of which almost five-sixths of the expense of watering may be saved. It appears that the cost for labor in watering the streets of London averages about $675,000 per annum, the cost of water being additional; and it is contended that this work can be done in a far more effectual and advantageous manner, by a system of permanent pipes, for an expenditure of less than $15,000 per annum, while the interest upon the plan necessary for the purpose would not exceed $100,000. An experiment made in Hyde Park warrants the conclusion that, with the permanent system referred to, the services of one man would be amply sufficient for laying the dust over the whole of the drives and rides in that park—a task which at present engages twenty men, with as many horses and carts. This area may be taken as a seventy-fifth part of the total road-way in London to be watered; and hence we may conclude that about seventy-five men, without either horses or carts, could water the whole metropolis at the cost for labor above stated. The city government of London is giving the matter serious consideration; and, if water is to continue in use for the purpose of laying dust on thoroughfares, the plan will doubtless be generally adopted on being proved practicable. It is to be hoped, however, that before long deliquescent salts will be employed for this purpose rather than water. The use of water in summer hastens the decay of organic matter, and thus is objectionable from a sanitary point of view. Deliquescent salts will not alone lay the dust, but will also disinfect the streets by checking decomposition.

French Association for the Advancement of Science.—The French Association met at Lyons, on August 21st, the opening address being made by the president, Quatrefages. He traced the history of scientific progress during the past hundred years, and advocated the claims of science as an important branch of general education. The reports of the secretary and treasurer show that the Association is in a flourishing state, and that it has already, in its second year, commenced to give material encouragement to original investigators of science. The most notable of the papers read in the general meetings were the following: Dr. H. Blanc, Surgeon-Major of the British Army, on "The Means of guarding against Cholera: an Essay based on Practical Knowledge of the Causes and Mode of Propagation of that Disease;" Fernand Papillon, on "The Relations between Science and Metaphysics;" the Abbé Ducrost, on "The Prehistoric Station of Solutré;" and Dr. Bertillon on "The Population of France."

One of the sections of the French Association is devoted to the medical sciences. In this department, the most remarkable papers were those of M. Ollier, on "The Surgical Means of favoring the Growth of the Bones in Man;" M. Chauveau, on "The Transmission of Tuberculosis through the Digestive Organs;" M. J. Gayet, on "The Regeneration of the Crystalline Lens;" and M. Diday, on "A Physiological Theory of the Passion of Love."

In anthropology, we may mention M. Lagneau's "Ethnological Researches on the Basin of the Saone and Other Affluents of the Rhone;" M. Chauvet's "Observations on the Bone-Caves of Charente," Gabriel Mortillet and Abel Hovelacque on "The Precursor of Man in the Tertiary Period."

The chemical section presents matter of special interest only for chemists. In that of botany, M. Merget read a paper on "The rôle of the Stomata in the Exchange of Gases between the Plant and the Atmosphere."

The Cryptograph.—A very ingenious instrument, the cryptograph, was recently described by its inventor, Pelegrin, in a note communicated to the French Academy of Sciences. The cryptograph is a contrivance intended for noting down on the spot and converting into mathematical expressions, so that they may be sent directly and secretly by telegraph, the polar coordinates of the points which determine a given figure. By means of this instrument, one may—at New York, for instance—trace out figures seen and noted down by a correspondent at any point in telegraphic communication with him. The cryptograph consists of a graduated arc of a circle, and an alidade, or index, also graduated and movable over the entire arc. The alidade has attached to it a small, thin plate of mica, which may slide up and down its entire length. On the mica is a black point, and this, it is plain, may occupy every possible position within the arc. A sight is fixed in front of the instrument. In order, now, to note down the outlines of a given figure, the observer places his eye at the sight, and brings the black speck on the mica over all the chief points, and marks their polar coördinates, as shown by the positions of the alidade and the sliding-point. These numbers may then be transmitted by telegraph anywhere. With the assistance of another cryptograph, in which the mica is replaced by a style or pen, the points noted by the first instrument are at once found and copied on paper.

Localization of the Faculty of Speech.—In a recent memoir on the localization of the faculty of speech in the anterior lobes of the brain, the eminent physiologist Bouillaud communicates to the French Academy of Sciences the results of his protracted researches on that subject. Some of the cases cited by him in the course of the memoir are extremely curious. In some instances, says he, the inability to speak is restricted to a certain class of words—certain proper names, for instance; in others, it extends to all past events; in others, again, only prominent circumstances are involved; and so on. Cuvier tells of a man who had lost the recollection of all nouns-substantive, and who would construct his phrases perfectly and regularly, the places of the nouns being always left vacant. Some years ago, M. Bouillaud visited a patient whose vocabulary did not contain a single verb, but who, notwithstanding, talked with remarkable volubility: his language was, of course, perfectly unintelligible. Others are unable, of their own accord, to write some particular word—house, for instance—though they can copy it when it is placed before them. A lady, forty-three years of age, was suddenly deprived of the power of speech, and entered the Cochin Hospital; she heard and understood perfectly every thing that was said to her, but could not speak. She could express herself in writing, however, and thus it was learned that she suffered pain in the forehead. From these cases, it follows that aphasia is produced by an incapacity to execute the coördinate movements requisite for pronunciation, and that it has nothing to do with loss of memory as to the meaning of words.

According to M. Bouillaud, these phenomena are produced by lesions of the anterior cerebral lobes. He claims that his theory is confirmed by the results of several autopsies, and asserts that, wherever he has had an opportunity to examine the brain of patients affected in this way, he always found the anterior lobes softened, inflamed, and more or less profoundly disorganized. These views gave rise to a warm discussion when they were first published to the Academy, and Flourens contributed an important memoir on the subject, in which he took the ground that while the cerebral lobes possess the faculties of will and perception, they do not coordinate movements, the latter function appertaining, according to him, to the cerebellum.

M. Bouillaud sums up as follows the conclusions to which he has been led in the course of his studies: 1. All lesions of the faculty of speech have their origin in affections of the frontal lobes. In some instances, this lesion to the faculty of speech is owing to the fact that the coördinated movements requisite for the pronunciation of words cannot be executed. Therefore, there exists in these anterior lobes a coördinating centre for this description of voluntary movements. In other instances, lesions of the faculty of speech have a bearing on the words themselves, and not on the act of pronouncing them. Therefore, there exists in the same lobes another centre, without the coöperation of which speech is impossible.

2. When either or both of these conditions exist, the faculty of speech may be injured or utterly lost, while all the other special intellectual faculties remain intact, and vice versa.

The Rebuilding of Antioch.—In the rebuilding of the city of Antioch, destroyed by earthquake last year, the chief engineer of the province of Aleppo, Mr. Haddan, an Englishman, did his best to induce the people to profit by the experience of the past, and to construct their houses and lay out their streets in such a manner that the recurrence of earthquake might not again prove so destructive. But immobility is the law of the East, and the people will not quit the ancient paths. It is a significant fact, says the Builder, that many of the victims on the occasion of the last earthquake might have escaped, if the houses had been built with lime or bound with wood, and if the streets had not been so narrow that the rows of falling buildings met as they crumbled down, to form one destructive heap over the crowds of people. Mr. Haddan proposed that skeleton houses should be erected with timber battens, well tied together with iron bands, on which overhanging roofs would rest. Stone-walls, cemented with lime, were then to be run up around the wooden frames, in order to afford protection from sun and rain. A shock of earthquake (which is a matter of frequent occurrence at Antioch), how formidable soever it might be, could then do no more than throw the stone-walls outward, while none of the falling stones could injure those in the houses. The new plan of the town, by straightening and widening the labyrinth of tortuous lanes which previously existed, would save the inhabitants from much of the danger after escaping from their houses. But, as has been already said, these suggestions have been disregarded, and the town is beginning to rise again on its old foundations, built with mud instead of lime, and likely to destroy its future population in even greater proportion than it did last year, for increased poverty makes the new houses weaker than even the old ones were.

Intelligence of the Toad.—At the recent meeting of the American Association for the Advancement of Science, held at Portland, Mr. Thomas Hill read a note on the intelligence of toads, giving, among other interesting examples of their sagacity, a description of the means by which the creature contrives to force down inconvenient forms of food. "When our toad," says Mr. Hill, "gets into his mouth part of an insect too large for his tongue to thrust down his throat (and I have known of their attempting a wounded humming-bird), he resorts to the nearest stone," and uses it as a pièce de résistance in a very literal sense. This can be observed at any time, continues the author, by tying a locust's hind-legs together, and throwing it before a small toad.

On one occasion Mr. Hill gave a small locust to a little toad in its second summer. At once the locust's head was down the creature's throat, the hinder parts protruding. The toad then sought for a stone or clod; but, as none was to be found, he lowered his head and crept along, pushing the locust against the ground. But the ground was too smooth (a rolled path) and the angle at which the locust lay to the ground too small, and thus no progress was made. "To increase the angle, he straightened up his hind-legs, but in vain. At length he threw up his hind-quarters, and actually stood on his head, or rather on the locust sticking out of his mouth, and, after repeating this once or twice, succeeded in getting himself outside his dinner."

On another occasion the author saw an American toad disposing of an earthworm in the following way. The worm was so long that it had to be swallowed by sections. But, while one end was in the toad's stomach, the other end was coiled about his head. "He waited until the worm's writhings gave him a chance, and swallowed half an inch; then, taking a nip with his jaws, waited for a chance to draw in another half-inch. But there were so many half-inches to dispose of that at length his jaws grew tired, lost their firmness of grip, and the worm crawled out five-eighths of an inch between each half-inch swallowing. The toad, perceiving this, brought his right hand to his jaws, grasping his abdomen with his foot, and, by a little effort getting hold of the worm in his stomach from the outside, he thus, by his foot, held fast to what he had gained by each swallow, and presently succeeded in getting the worm entirely down."

The Sun's Envelope.—Prof. Charles A. Young's paper, read at the American Association, on a liquid solar crust, led to a very animated discussion. The author is inclined to hold, with Faye, Secchi, and others, that the sun is mainly gaseous. At the same time, the eruptions which are continually occurring on its surface almost compel the supposition that there is a crust of some kind which retains the imprisoned gases, and through which they force their way in jets with great violence. According to the author, this crust may consist of a more or less continuous sheet of descending rain—that is, a downfall of the condensed vapors of those materials which we know from the spectroscope exist in the sun. The continuous efflux of the solar heat is equivalent to the supply that would be developed by the condensation from steam to water of a layer of about five feet thick over the whole surface of the sun every minute of time. As this tremendous rain descends, the velocity of the falling drops would be retarded by the resistance of the denser gases underneath; the drops would coalesce until a continuous sheet would be formed; and these sheets would unite and form a sort of bottomless ocean resting on the compressed vapors beneath, and pierced by innumerable ascending jets and bubbles. It would have an approximately constant depth, because it would turn to vapor at the bottom as rapidly as it grew at the surface, though probably the thickness of this crust would continually increase at a slow rate, and its whole diameter grow less.

In other words, Dr. Young would regard the sun as an enormous bubble whose walls are steadily thickening, and its diameter ever lessening, in proportion to the loss of heat. The hypothesis offers no peculiar explanation of the sun-spots, but will agree with any of the current explanations of that phenomenon.