Popular Science Monthly/Volume 13/July 1878/Popular Miscellany

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POPULAR MISCELLANY.

Fossil mammal from the Jurassic of the Rocky Mountains.—One of the most interesting discoveries made in the Rocky Mountain region is the right lower jaw of a small mammal recently received at the Yale College Museum, and described by Prof. Marsh under the name Dryolestes priscus. The specimen was found in the Atlantosaurus beds of the upper Jurassic, and the associated fossils are mainly Dinosaurs. The specimen is in fair preservation, although most of the teeth have been broken off in removing it from the rock. The penultimate molar, however, remains in place. The shape of the jaw and the position and character of the teeth show that the animal was a small marsupial, allied to the existing opossums (Didelphidæ). The tooth preserved has the same general form as the corresponding molar of Chironectes variegatus (Illiger). The angle of the jaw is imperfect, but there are indications that it was inflected. The present specimen indicates an animal about as large as a weasel. It is of special interest, as hitherto no Jurassic mammals have been found in this country.

 

Threatened Outbreak of Vesuvius.—Mount Vesuvius is giving signs of an approaching season of great volcanic activity. A bulletin issued by Prof. Palmieri states that the new mouth, which opened at the bottom of the crater in 1872, and which has been more or less active since December 18, 1875, began on May 2d last to give indications of being still more active. The fire cannot be seen from Naples, as it is at the bottom of the crater, and only its reflection is visible on the smoke which rises from it. This reflection is of course greater when the bellows of Vulcan blow up a stronger flame. The smoke, which abounds in acids, mingled with rain-water, is extremely injurious to vegetation, particularly in the direction of Ottaiano, where the vintage has been destroyed for nearly two years. So long as the eruption continues to be central, a long time must elapse before the lava will roll down the sides of the cone, as the cavity of the crater is far from being full. But, should the cone be opened laterally by some extraordinary eruptive force, then the lava will pour out in a deluge.

 

The Organ-Piano.—Many are the devices that have from time to time been contrived for the purpose of giving to the notes of the piano the "sustained" character possessed by those of the organ. For whatever reason, none of these contrivances have hitherto met with general acceptance, and "organ-pianos" are as yet merely curiosities. But an instrument of this kind is now on exhibition in Paris, which appears to be of practical value, and for which there is already a good demand. There is a brief description of this "organ-piano" in Nature, from which we take the following particulars: In this instrument the "organ" or prolonged sounds are produced by a succession of extremely rapid hammer-blows. Besides the usual piano-hammers, the piano-organ has a series of additional hammers (one to each string), mounted on watch-spring levers, all of which are carried by a bar of brass lying across, but above and clear of, the strings. To this bar is attached a rocking lever which is set in very rapid motion by means of an apparatus worked easily by a pedal. The pianist works the pedal, and thus sets the transverse bar with its series of hammers into excessively rapid vibration. By holding down any key of the instrument, the string belonging to it is brought within range of its corresponding hammer, and is struck with corresponding rapidity, giving out what sounds at a short distance like one prolonged note, lasting as long as the pedal is worked and the key is kept down. In this way the performer can produce either piano or organ notes at will.

 

Sun-Worship among the Moquis.—Traces of sun-worship still exist among the inhabitants of the Moqui villages in Arizona. They have lost the substance of the antique religion, but they retain a portion of the ceremonial—the watching for the emergence of the day-god in the eastern horizon. But it is not the sun they now watch for, but Motecuhzuma (Montezuma), their Messiah, so to speak. Mr. Edwin A. Barber, in the American Naturalist, describes as follows the impressive scene witnessed every morning at dawn in the Moqui villages: "As the faint streak of red lights up the low horizon, tall, dark figures appear on the parapets of the seven Moqui towns "(a description of which was given in Vol. VI. of the Monthly), "and remain facing the dawn until the sun has appeared entirely to view. Then the muffled forms drop away slowly and sadly, one by one, for another morn has brought disappointment to the souls of many that have watched so eagerly and persistently for the coming of the great Montezuma. The routine of another Moqui day has commenced; all is bustle and life, and the subdued hum of household occupation floats out drowsily on the sullen, sultry air, and the sound of the hundred flour mills (metates), grinding steadily on every side, seems, as it issues from the doors and windows of the stone houses, to pause in mid-air like a droning bee. Then scores of busy figures repair with their water-vessels to the verge of the steep bluffs, and disappear in the crevices of the rocks below."

 

How Monkeys dislike Snakes.—That monkeys, like man, have a peculiar instinctive abhorrence of snakes, is shown by an experiment made in the Philadelphia Zoological Garden by Mr. Arthur E. Brown, and recorded in the American Naturalist. Mr. Brown having wrapped a dead snake in paper, set the package on the floor of a cage containing forty or fifty monkeys. It was instantly spied by a female cynocephalus, who quickly seized the paper and dragged it away with her. Soon the paper unfolded and the snake slipped partly out. On seeing what the package contained, the cynocephalus instantly dropped it and sheered off. The other monkeys now cautiously approached the dead snake, but all were careful not to come too near, with the exception of one, a large macaque, who would make an occasional snatch at the paper, as though to see whether the dreaded animal were really dead. A pull on a string attached to the tail of the snake, causing it to stir, sent the inquisitive monkeys scampering away, but they would again return, ever keeping at a respectful distance. The dead snake was then successively introduced into cages occupied by animals of other orders—carnivores, rodents, ungulates, etc.—but none of them paid it any special attention except one peccary, which, finding that it was dead, seemed disposed to eat it. The author observed in a deaf and dumb lady the expression of the same emotions and feelings, on beholding serpents, which had been exhibited by the monkeys. There were the same fear, the same attraction and repulsion; and after watching for a long time, with an expression of intense disgust, a cage of boas, she was led away by her friends, protesting that she wanted to stay.

 

Discoloration of Brick Walls.—Brick buildings, in the neighborhood of New York, are often seen disfigured by streaks and patches of white; but it is in Philadelphia that the evil is most noticeable. There these white incrustations are very general on brick house-fronts, and the study of their causes and their remedy has for some time engaged the attention of builders. Mr. William Trautwine is, so far as we know, the first who has attempted a thorough, scientific investigation of the subject; and his observations, published in the Journal of the Franklin Institute, are eminently worthy of the attention of architects in localities where this disfiguration makes its appearance. The evil, he says, is most noticeable in dry weather on parts of walls subjected to dampness, and on entire walls after rain-storms have soaked them. The white coating is derived primarily from both the bricks and the mortar. In some instances it undoubtedly comes from the bricks; here the white substance is dissolved by moisture from the bricks even before they are built into the houses. The author has found it in bricks just from the kiln. It has a peculiar taste—that of sulphate of magnesia; but besides this salt the bricks also contain sulphate of lime. The author's theory is that the silicates of magnesia and lime in the bricks are converted into the sulphates by the sulphuric acid evolved from the sulphide of iron and iron pyrites contained in the coal which is employed in the kilns. Now, sulphate of magnesia effloresces in dry air, and sulphate of lime is dissolved by moisture and appears on the surface of the bricks. Hence, plainly, one mode of preventing the incrustation is the employment only of wood or of coke free from sulphur in the kilns—at least this might be done in the manufacture of pressed brick for house-fronts. As for the incrustations having their origin in the mortar, the author remarks that sulphate of magnesia is largely produced by the decomposition of mortar. His observations on this head have special application to Philadelphia and its vicinity, where most of the lime used in building is from magnesian limestone. The resulting mixture of limestone and magnesia, when slaked and made into mortar, is very susceptible to the influence of sulphurous fumes in the atmosphere, which produce in the mortar sulphates of lime and magnesia. The great solubility of sulphate of magnesia facilitates its diffusion; sulphate of lime is comparatively insoluble, and does not cause so much disfigurement. Of course, mortar made with lime from magnesian limestone quickly decomposes, and the bricks it was intended to cement become loose. The remedy for this evil is the employment of lime from non-magnesian limestone.

This explanation of the phenomenon of incrustation is pronounced to be the correct one by the editor of the Polytechnic Review, who also approves Mr. Trautwine's proposed remedy for the evil. At the same time he offers, on theoretical grounds, a simpler remedy, which he proposes to have subjected to the test of practical experiment. This remedy is the addition of a small quantity of baryta to the water used for tempering the brick-clay. The rationale of this process we will state as briefly as possible, mainly in the author's own words: The incrustation being due to the process of soluble sulphates, caused by the decomposing action of sulphuric acid on the magnesia and lime silicate in the clay, the presence of a small amount of free baryta would either altogether prevent or at least greatly reduce the amount of this decomposition. The baryta, having a strong affinity for the free acid, would seize upon it, and with it form insoluble sulphate of baryta. Even though the free baryta did not altogether prevent the formation of the soluble sulphates, it is safe to assume that there will be present in the finished brick sufficient uncombined baryta to decompose and cement into insoluble barium sulphate such soluble magnesia and lime sulphates as may have been formed during the process of burning, so soon as these sulphates are dissolved by moisture. A like addition of baryta to mortar after it is prepared for use may reasonably be expected to check the tendency to efflorescence, except of course where the mortar, as in chimneys, is continuously exposed to the action of sulphurous vapors.

 

An Interesting Experiment.—A simple experiment, devised by Prof. A. M. Mayer, illustrates in a very effective way the action of the forces of attraction and repulsion on bodies freely moving in a plane, and serves to give clearness to our conceptions of molecular action. He takes a number of needles, of the size known as "number 6," and magnetizes them, giving to all the points the same polarity, say north. Then each needle is driven into a small cork float, so that it will keep the upright position in water, the eye just coming through the top of the float. If, now, three of the needles be dropped into a bowl of water, and the north-pole of a rather large cylindrical magnet be brought slowly down over them, the mutually repellant needles are made to approach one another, and then arrange themselves thus... Raise the magnet, and the needles go farther apart; lower it, and they come together again, the three needles always holding their places at the vertices of an equilateral triangle. Add needles successively, and the following arrangements will be seen, viz.:

PSM V13 D394 Magnetic experiment.png

The needles can be made to assume the arrangements shown in the second column, but these figures are not stable. So long as the magnet is held directly over them, the needles will remain in the positions indicated; but raise it, so as to let the needles go apart, and then bring it down again quickly, and in all probability the figure given in the first column will be the result. Prof. Mayer has obtained the figures up to the combination of twenty needles. He adds, in a note to the American Journal of Science: "These experiments can be varied without end. It is certainly interesting to see the mutual effect of two or more vibrating systems, each ruled more or less by the motions of its own superposed magnet; to witness the deformations and decompositions of one molecular arrangement by the vibrations of a neighboring group; to note the changes in form which take place when a larger magnet enters the combination, and to see the deformation of groups produced by the side action of a magnet placed near the bowl."

 

Experiments with the Electric Light.—A public exhibition was recently made in Cleveland, Ohio, of an electric-light machine invented by Mr. Charles E. Brush, of that city. The results were in the highest degree satisfactory, as will be seen from the following account of the experiment which we condense from the Cleveland Herald:

The machine is capable of giving a light of 12,000 candle-power, the electric fluid being distributed to four electric lamps, each having the power of three thousand candles. The exhibition was given in the establishment of the Union Steel Screw Company, where two of the lamps were placed on the third and two on the fourth floor of the immense building. The illumination was perfect. The rooms were flooded with a pure white light like the light of the sun, and it streamed out at all the windows, illuminating houses and streets for a long distance in every direction. The light was very uniform and steady, free from the flickering that used to be an accompaniment of electric light, and, considering the enormous illuminating power, the light was unexpectedly soft and endurable to the eyes. An opportunity was afforded to test the character and whiteness of the light. Worsteds, scarfs, afghans, etc., of brilliant shades were hanging against the wall at one side of the room, and it was noticed that the colors were brought out as clearly as by the full light of the sun. Estimates were made as to the amount that the light furnished by this apparatus would cost, if used by the Screw Company as it was used on the evening of the exhibition, and it was ascertained that the total cost of the whole light from the four lamps, including the items of consumption of carbon in the lamps, interest on the investment, and wear and tear, would not exceed thirty cents per hour. The light produced was photometrically equal to eight hundred gas-burners, burning five feet of gas per hour each. This amount of gas would cost eight dollars per hour in Cleveland.

 

Ascent of Mount Ararat.—In September, 1876, Mr. J. Bryce made the ascent of the greater peak of Mount Ararat, and at a recent meeting of the London Geographical Society gave an account of the feat. Mount Ararat is situated nearly in the centre of the region known as Armenia—a territory divided between three empires, and lying round the sources and upper courses of the Araxes, Euphrates, and Tigris. The mass of Ararat is about twenty-five miles long from northwest to southeast, and from twelve to fourteen miles wide. It consists of two peaks joined together by a sort of neck. The greater peak, Great Ararat, rises 17,000 feet above sea-level, and the lesser peak, Little Ararat, 12,800 feet; both are of volcanic origin. Mr. Bryce began the ascent from a small Tartar village on the northeastern face of Great Ararat, being accompanied by a friend and two guides, a Cossack and a Kurd. At the height of about 11,500 feet Mr. Bryce's friend abandoned the attempt to reach the summit. The remainder of the climb had to be made over beds of snow, and over bare, loose, broken stones; the latter course Mr. Bryce chose. At the height of 15,000 feet the Cossack and the Kurd refused to go any farther, so he was compelled to journey alone. The last part of the ascent was upon a slope of rotten rocks, rather soft and sulphurous, which crumbled under his feet, adding greatly to his fatigue. Near the top of this slope Mr. Bryce could just discern the edges of the plateau of snow, and hanging on this a curtain of clouds. After ascending into these clouds two strong blasts of wind swept them away, and then a wonderfully grand and extensive view lay before him. The Caucasus could be seen to the north, distant about 250 miles; the highest ranges of mountains round Erzeroum to the west; the mountains of Assyria, and South Kurdistan, the mountains in the direction of Nineveh, and the valley in the direction of the Zab, to the south; to the east, the enormous mountain-masses in Persia, and north as far as the Caspian. But in his fondest anticipation Mr. Bryce was doomed to a sad disappointment: he could find no fragment of Noah's ark!

 

Prevention of Contagions Diseases.—Two modes of fortifying the system against the attacks of zymotic disease are pointed out by Dr. E. M. Hunt, in the Medical Record, viz.: topical application of substances inimical to the development of contagia; and, secondly, the introduction into the blood of substances which shall prevent fermentive, defibrinizing or destructive processes. On the hypothesis that contagium vivum is introduced into the human system from without, and mostly through the inbreathed air, the author advocates the charging the mouth and nostrils with antiseptic substances so as to render the breath and the tissues more immediately exposed unfriendly to the development of the contagium. When the floating infective particle presents itself either for local manifestation or for absorption, it may require "but slight unfriendliness of reception to prevent morbid result." In diseases like diphtheria and scarlet fever, which at the outset have such marked local manifestation as to lead us to believe that they are local before they are constitutional, topical application of remedies seems to be clearly indicated. But the author thinks that the introduction of certain substances into the blood is a still more effectual mode of combating contagia. In this way not only are the portals of entrance protected, but the fluids, glands, etc., of the system are so permeated with the antiseptic or antifermentative agent as to be able to withstand the action of the disease-germ. How much may be due to the local hinderance to fertilization, and how much to the constitutional resistance established, may not in each case be easy to determine. But when we consider how readily chlorate of potassium, after being administered, is found in the secretions, how soon a few grains of pure protochloride of iron increase the number of the red globules of the blood, how defibrination of the blood is retarded by certain agents, we are justified in the hope that our power to suspend the action of disease-poisons will yet be greatly augmented.

 

Creosote as a Timber-Preserver.—Railway-ties, dried, and saturated with creosote, will last, according to Mr. E. R. Andrews, for twenty years or more in good condition. In ties so treated the spikes intended to hold the rail do not corrode nor work loose. Then, too, the surface of the tie under the rail does not decay nor wear, because it is not affected by alternate dryness and moisture. In the construction of wharves and in ship-building, creosoted timber is also of great advantage. It is proof against the ravages of the Teredo navalis and other mollusks which cause such destruction of timbers submerged in sea-water. The woods best adapted for the creosoting process are those which are light and porous, as these most readily absorb the creosote; so treated they become more solid and enduring than the most costly species of timber. "The cottonwood of the Southwest," writes Mr. Andrews, in the American Gaslight Journal, "can be made as useful as oak for ties. White pine absorbs creosote like a sponge, and the yellow pine of the South takes it readily also. In England fir from the Baltic is used altogether for ties, and I do not see why the despised fir from our forests may not be used for the same purpose here. Hemlock is good also; spruce is a firm, compact wood, and absorbs oil with more difficulty; neither does it require so much to preserve it. Oak has a coarse fibre, and is easily treated."

 

The Eyes of Deep-Sea Animals.—In giving to the National Academy of Sciences an account of recent dredging and sounding in the Gulf of Mexico, Prof. Alexander Agassiz referred to the question of sight in marine animals living at great depths. He said that the crustaceans and fishes taken from depths of from 1,500 to 1,900 fathoms or more present conditions diametrically opposite to one another with respect to vision, some of these creatures being eyeless or nearly so, others having eyes enormously developed, as if to enable them to see with the faintest glimmer of light. In the former class many very curious modifications of structure are to be seen taking the place of the eyes. The existence of these very wide differences of structure under identical conditions he regarded as strange, but, in the discussion which followed the reading of the paper, Profs. Cope and Gill held that this difference was precisely what we might expect, according to the evolution hypothesis. There is nothing surprising in the fact that in one set of animals "survival of the fittest" should work obliteration, and in another class abnormal development of the visual organs.

 

Studies of Embryo Life.—On opening the shell of a hen's-egg in the third day of incubation, Harvey noticed the heartbeats of the embryo, which, however, soon ceased. He then placed the egg in warm water, and the heart commenced to beat again. The same experiment, but with important modification, has been repeated by M. Dareste, who for some years past has devoted himself with great assiduity to the study of embryo life. He took from under a hen an egg on which she had sat for three days, and let it remain in the ordinary temperature for two or three days. He then again placed it under conditions favorable to incubation, and in due time a chick was hatched out, just as if there had occurred nothing unusual in the mean time. The result of this ingenious experiment, as M. Stanislas Meunier observes in La Nature, is to show that life may be suspended for a considerable length of time in warm-blooded animals without fatal effects, precisely as in animals of a very low grade, such as Rotifera.

 

Mars's Fast Moon.—The periodic time of the inner satellite of Mars is only very little over seven hours, while the axial rotation of Mars itself requires about twenty-four hours. Now, this discrepancy is in apparent conflict with the nebular hypothesis, which assumes all the secondary bodies of a system to have been evolved from their primary at successive stages, with the velocity of the primary's surface at the time of their being dropped as rings of nebulous matter. But here is a planet's satellite possessed of a velocity of revolution more than thrice as high as the velocity of axial rotation possessed by its primary. The problem, how to account for this accelerated movement of the inner Martial moon, has occupied the attention of astronomers since the discovery of Mars's satellites by Prof. Asaph Hall, a few months ago. The theory proposed by Prof. M. H. Doolittle, of the Coast Survey, appears to solve all the difficulties of the case. In three ways, according to Prof. Doolittle, the relative velocities of Mars and his moon might be modified by the impact of interstellar matter, or meteorites: 1. These bodies, by striking the satellite and forcing it to travel in a narrower orbit, its original absolute velocity continuing the same, would increase its relative velocity; 2. By striking the primary, they would increase its mass and its attraction on the satellite; 3. By increasing the mass of the primary and so reducing its absolute velocity they would make the relative velocity of the satellite higher.