Popular Science Monthly/Volume 27/September 1885/Popular Miscellany

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Industrial Education in Common Schools.—Mr. B. B. Huntoon recently read a paper before the "Conversation Club" of Louisville, Kentucky, on "Industrial Education," in which he advocated the introduction of the Russian system into the public schools. This system does not aim to teach the practical exercise of particular arts, but only so to train the eye and hand to the execution of designs and the use of tools that the pupil may be qualified to take up readily what-ever art he may afterward choose to follow. The system, in its most essential features, has already been tried successfully in the Massachusetts Institute of Technology; Washington University, at St. Louis; Purdue University; Illinois University; Tulane University, New Orleans; and in industrial schools in Chicago, Baltimore, Philadelphia, and New York city; and in Boston and Gloucester, Massachusetts, and Montclair, New Jersey, the experiment has been tried of incorporating a course of industrial training upon the city schools. Mr. Huntoon believes that the people are ready to be taxed for such a purpose; that there will be no difficulty in finding teachers; and that the scheme is entirely practicable.

The Pittsburg Natural Gas-Wells.—According to the account recently given by Mr. Andrew Carnegie to the Iron and Steel Institute, the principal district in which the natural gas-wells near Pittsburg are found, the Murraysville field, lies to the northeast of that city, running southward from it toward the Pennsylvania Railroad. Nine wells had been sunk there last fall, and were yielding gas in large quantities. Gas has been found in a belt averaging about half a mile in width for a distance of between four and five miles. Beyond this a point is reached where salt-water flows into the wells and drowns the gas. The gas-fields of Washington County are about twenty miles from the city, swinging round toward the south-west. Four wells are now yielding gas in this district, but are not, perhaps, so strongly charged as those of the Murraysville district, and others are being drilled. Still farther to the west is another gas territory, from which manufacturing works in Beaver Falls and Rochester receive their supply. Next is the Butler gas-field, as far from Pittsburg on the northwest as are the Washington County wells on the southwest. Next, on the Allegheny River, is the Tarentum district, still about twenty miles from Pittsburg, which is supplying a considerable portion of the gas used. Thus, within a circle around Pittsburg having a radius of fifteen or twenty miles, there are four distinct gas-producing districts. Several wells have been bored within the city; but, though they all yielded gas, it has been drowned out by the rush of salt-water. While the largest well known yields about 30,000,000 cubic feet of gas in twenty-four hours, the average product of a good well may be set at about half of this. The pressure of the gas as it issues at the mouth of the well is nearly or quite two hundred pounds per square inch. Even at the works of the company represented by Mr. Carnegie, nine miles from the well, the pressure is seventy-five pounds per square inch. Eleven lines of pipe are conveying gas from the various wells to the manufacturing establishments in and around Pittsburg. Although it is only two years since gas has been used in Pittsburg, it has already displaced 40,000 bushels of coal per day in the mills that have used it, and about an equal amount has been displaced in the works beyond the city limits. Contracts are now made to supply houses with gas at a cost equal to that of the coal bill for the preceding year. In many houses, no other fuel than this gas is used; and everybody who has applied it to domestic purposes is delighted with the change from the smoky and dirty bituminous coal. It is, therefore, Mr. Carnegie suggests, quite within the region of probability that the city, now so black, may become so revolutionized as to be the cleanest manufacturing city in the world.

English Board-School Science.—Dr. Andrew Wilson's "Health" has been struck with some of the answers in the schoolchildren's examination-papers in popular science, and gives a few specimens of them. Among them are—"the humerus (or upper arm-bone) is known as the 'numerous,' and is often called 'the funny-bone.'" "The sweet-bread is otherwise called the paneras (for pancreas), which is so named from the Midland Railway Station in London." "A thermometer is an instrument used to let out the heat when it is going to be cold." "When roasting a piece of beef, put it in front of a brisk fire, so as to congratulate the outside." "Sugar is an amyloid. If you were to eat much sugar and nothing else, you would not live, because sugar has not got no carbon, hydrogen, oxygen, nitrogen. Potatoes is another amyloids." Very interesting is the description of digestion given by one of the pupils: "Food is digested by the action of the lungs; digestion is brought on by the lungs having something the matter with them. The food then passes through your windpipe into the pores, and thus passes off you by evaporation, through a lot of little holes in your skin called capillaries. The food is nourished in the stomach. If you were to eat anything hard you would not be able to digest it, and the consequence would be you would have indigestion. The gall-bladder throws off juice from the food which passes through it. We call the kidneys the bread-basket, because it is where all the bread goes to. They lay concealed up by the heart."

A Story of Two Rats.—A correspondent of "Land and Water" tells a story of two white rats which he had adopted as pets. The male was a quiet, commonplace sort of rat, acquaintance with whom afforded few incidents of particular interest. The female was a great coquette, and a regular domestic tyrant, exercising absolute control of her spouse and household. Always pleased with the gift of some dainty, she was "rapturously delighted" if allowed to think she had stolen it. If the master would have a piece of sugar on the table, she would creep up and take it, retreating behind a book to devour it, as she hoped, unobserved. She was a relentless enemy to mice; and, when one of these animals was put into her cage, "she flew at it and slew it with a single bite, leaving it instantly, as a well-trained terrier does the rat it has killed." The first occasion of Anna Maria having little ones was quite an event. "When I went to the box, as usual, to give my little rodents a scrap of whatever I might have had, I found Augustus (the male) sitting out in the cold and looking terribly sheepish. On opening the sleeping compartment, there was Anna Maria, with something like a smile upon her shrewish little countenance, keeping watch and ward over nine ridiculously naked little offspring. On these occasions Augustus was completely effaced. He shirked the slightest responsibility; and I always had to make him up a separate bed, for sleep with his children he would not. If by chance he was forced to walk among them, he did so with an anxiety that would have done credit to an elephant stepping between eggs. As they grew up, assumed hair, and began to run about, he would allow them to take liberties with him, and even rob him of tidbits." The master thought the hay the naked little fellows were lying upon too rough for their tender skins, and put wadding in its place. "But, with a sneer of contempt for the stupidity of men in such matters, Anna Maria promptly cast out the wadding and bumped her progeny upon the hay again." In washing them, "she would roll them over and over with her paws, and lick them till the sparks flew, and they would utter plaintive little squeaks." But they throve splendidly. "Every night this graceful couple gamboled about my table while I read or wrote. It was a delight to me to watch them at their toilet or eating the food which they held in their delicate little paws. . . . When tired of play, they would clamber up to my shoulder and slumber, huddled together like two love-birds." Anna Maria at last died of a cold, and her place was supplied by a new female, whose chief peculiarity was that as soon as she had a family she would bite off her babies' heads."

Cannibalism among Rats.—Mr. W. Mattieu Williams believes that rats are, upon occasion, voracious cannibals, devouring one another by wholesale and without mercy. Being troubled beyond endurance by these pests, and getting no relief from dogs, ferrets, and cats, and fearing poison, he tried the effects of stuffing the holes with broken glass. "This was successful, and some curious results accompanied the clearance. At first, there were streaks of blood on the kitchen-floor in considerable quantity, and distributed all over it. These appeared on several mornings. At about the same time, and subsequently, much scampering and screaming was heard beneath. This was followed by a rapid reduction of the number of the enemy. My theory," says Mr. Williams, "is, that when any one rat was wounded by the glass, the scent of blood excited the voracity of the others, and a cannibal struggle occurred; that this continued till extirpation followed—the more fighting, the more bloodshed and the more cannibalism." Mr. F. W. Halfpenny partly confirms this view in "Science Gossip," where he says that the black rat is still to be met with at most of the London docks; that the Norway or sewer rat not only kills its victim, but devours it. He describes skins of freshly killed black rats turned inside out, and found in various drawers, boxes, etc., and states that this treatment of their victims is usual with rats. As an experiment, Mr. Halfpenny gave the carcass of a white rat to one of the black and white variety. It was eaten, only a few bones of the head remaining attached to the everted skin.

Coal-Dust in Fire-Damp Explosions.—The Royal Prussian Fire-damp Commission has carried out a series of experiments in the Royal Coal-Mine near Neunkirchen, the results of which go far to confirm Mr. W. Galloway's theory of the agency of coal dust alone, and in conjunction with firedamp, in propagating explosions in mines. At the mine in question is a blower of firedamp at a depth of 131 yards below the surface, which gives off 0·9 cubic foot of gas a minute. For the experiments cannon were planted at the closed end of a horizontal gallery 167 feet long, having a branch 38 feet long, starting at a distance of 93 feet from its closed end. The branch gallery was closed at both ends with two-inch planking. One gun was fired when the gallery was free from fire-damp and from coal-dust; the flame of the shot was a little over 13 feet long. In a second experiment the floor of the gallery was strewed with coal-dust 1·17 inch thick for a length of 65 feet. The shot gave rise to a loud detonation, and the resulting flame filled the gallery to a distance of 881/2 feet. The inner planking of the branch gallery was broken. In the third experiment the gallery-floor was strewed with coal-dust for a length of 130 feet. The flame traversed the whole length of the gallery with great velocity, and came out at the open end to a distance of 16 feet, or 183 feet in all. It also emerged from the branch gallery to a distance of several yards. The outer partition of this gallery was broken into small fragments. For the fourth experiment, the partitions in the branch gallery were replaced, coal-dust was strewed on the floor for a distance of 65 feet, and a volume of 351/4 cubic feet of fire-damp was introduced and completely diffused. The firing of the shot produced a flame 190 feet long, accompanied by a report like a thunder-clap. The inner brettice of the branch gallery was broken and drawn several yards into the main gallery, but the outer one remained intact. The incidental effects of the last two shots also indicated how tremendous a force had been let loose when coal-dust formed one of the elements of the explosion. These experiments were typical of two hundred similar ones that had been made with from one to seven guns, all marked by results sustaining the coal dust theory.

Medical Virtues of Dog's Tongues.—M. Reimach having called attention to the mention, in the recently discovered inscriptions at the Temple of Esculapius, in Epidaurus, of children having been cured of blindness at that sanctuary by having their eyes licked by the sacred dogs, M. Henri Gaïdoz states that he has discovered the faith and practices of the dog-cure among several peoples and in a number of religions. The Hindoos believe that the English kill dogs to obtain possession of a sovereign remedy which is found in their tongues. In a Venetian legend, St. Roch was cured by a balsam distilled from the tongue of his dog. Dogs' tongues are considered to have medical virtue by many people in Portugal, France, and Scotland. In Bohemia they let dogs lick the faces of new-born children for "good luck." A belief in the existence of divinities issuing from dogs, whose office it was to lick the bruises of the wounded, once prevailed in Armenia. In a scene in one of Aristophanes's plays, Plutus recovers his sight in the Temple of Esculapius after being licked by two serpents which the god sent for that purpose in answer to his prayer.

Observations in the Sahara.—Dr. Oscar Lenz, whose account of his journey through Morocco, the Sahara, and the Soudan, to Timbuctoo, has been recently published, is the fourth European traveler who has reached the famous "Queen of the Wilderness," as the desert metropolis is called, during the present century. Having entered the city from the north, and then going from it westward and down the Senegal to the Atlantic coast at St. Louis, he has demonstrated the accessibility of Timbuctoo from both directions. One of the results of the surveys he made on his journey will probably be the death of the theory that the region of the Sahara has ever been a marine basin, at least since the early Tertiary epoch. The whole of the western section of the desert traversed by him was proved not to be a depression, as has been assumed, but an irregular plateau; standing in the north at a mean elevation of from eight hundred to one thousand feet, and even at Tandeni, its lowest level, still maintaining an altitude of four or five hundred feet above the Atlantic. The surface formations have nothing in common with marine sedimentary deposits, but are all evidently the results of weathering. The numerous dried-up water-courses, whose deep channels are distinctly the effect of erosion, also show that this part of the desert has been dry land for many ages. These wadies radiate from the central highland north and northeast to the Mediterranean, east to the Nile, south to Lake Chad and the Niger, and west to the Atlantic, and have been in their day full of water. Hence, it appears that, down to comparatively recent times, the Sahara was a well watered and wooded region, thickly inhabited by agricultural and pastoral communities. What has caused this change in climate? Dr. Lenz attributes it, not as Peschel has supposed, to the dry northeast polar winds (for these in the Sahara yield to the northern and northwestern atmospheric currents), but largely to the reckless destruction of the woodlands which once covered extensive tracts in the region.

Value of Fruit as Food.—The "Lancet" regards the increased use of fruit in ordinary diet as one of the most salutary tendencies of domestic management in our day. The starchy and saccharine components of fruit, while they are not equal in accumulated force to the more solid ingredients of meat and fat, are similarly useful in their own degree, and have the advantage of greater digestibility. Other advantages are the locally stimulant action of many sub-acid fruits, its control of a too active peptic secretion, and its influence of attraction upon the alkaline and aperient intestinal juice, to which further effects that aid the maintenance of a pure and vigorous circulation are indirectly due. "Thus it follows, on the simplest principles of physiology, that other essential organs, such as the skin and kidneys, are relieved by the transference of part of their excretory function to the bowel and act with greater ease, the general vascular system is lightened by this regulating drain, and its faculty of absorbing the waste products of food and work is encouraged in proportion." Only persons of gouty and rheumatic habit, or of tendencies to diarrhoea, dysentery, or saccharine diabetes, will be likely to find fruit in any moderate quantities to disagree with them, while dyspeptic persons will find it almost wholly beneficial.

Formation of Peat.—For the growth and formation of peat—which is vegetable matter in a semi-decomposed state—is required a climate sufficiently moist to foster the growth of the plants of the remains of which it is composed, and at the same time cool enough to retard, under certain conditions, the decomposition, beyond a certain point, of successive generations of those plants. Accordingly, we find it most abundantly distributed in latitudes above 45 in either hemisphere. In Ireland, the peat bogs cover about one seventh of the surface. Peat-bogs are classified as those which have ceased to grow and those which are still growing. Some of the former class must be of enormous age. In many bogs in Ireland the deposit is from fifteen to thirty feet deep, and in Scotland this depth is frequently exceeded. Each year's growth, according to Mr. Kinahan, is represented by a layer of lamina, and these lamina are, on an average, in white turf one hundred, in brown turf two to three hundred, in black turf from six to eight hundred to the foot. It is easy with these data to compute approximately the probable age of the bogs; but the result of the calculation is liable to variations according to the manner in which the bog was formed; for the rate of growth is subject to many fluctuations, not only in different bogs, but in different parts of the same bog. When two layers of wood are found in peat, the lower forest usually proves to have consisted of oak, and the upper one of pine. Remains of the great Irish deer are very common in the bogs of Ireland, and human relics are often found. No chronological estimates can, however, be based upon the presence of such relics, for articles having weight will easily sink through the soft mass. In districts where peat is plentiful it is extensively used for fuel, for which purpose the turf is cut from the bogs in narrow rectangular masses a foot or eighteen inches long, and prepared by drying. It is not well adapted for use in manufactures, for its heating power is low. Peat-charcoal has, however, been used with advantage in smelting iron, and it possesses very powerful antiseptic and deodorizing properties. Considerable quantities of peat-land have been reclaimed and brought under cultivation. In its natural state the soil is sour and unfit to promote plant-growth, but when drained and treated with lime it may be brought to a high degree of fertility. When the peat-bog is situated near to limestone, the process of reclaiming the land is cheap and the result is profitable.

A Scientific Commonplace-Book.—The purpose of "The Scientific Roll," a new serial kind of encyclopædia, or commonplace-book, projected and begun by Mr. Alexander Ramsay, is to cull, classify, and embody in a shape conveniently accessible, all the important statements of fact and theory that now lie scattered and substantially out of reach to any one man in the six thousand scientific periodicals of the day. The systematization of notes on this plan results in a most compendious classification of all that is wanted in scientific literature, in such a way that lines of thought are suggested to the reader, and facilities are offered for following them out which books, as a whole, do not afford. No correction is given, or comment upon the views of the several authors, but each one speaks for himself, and the reader is left to choose to what he will hold. The first volume, just published by Swan, Sonnenschein & Co., London, includes the literature of climate, in which a prominent place is given to a very interesting bibliography. One of the oldest works catalogued is said to have been written in the thirteenth century, and was printed by Caxton, under the title of "Image or Mirror of the World." But, as an English journal admits in its review of the publication, "it is not till we reach the year 1789 that we find the germ of the science, in a paper by Benjamin Franklin, under the somewhat timid title, for so bold a meteorologist, of "Meteorological Imaginations and Conjectures." This is followed by contributions from Lamarck, Saussure, Playfair, and Humboldt. The number of references to the year 1800, when Humboldt's name is first mentioned, is only three, while in 1880 the number has increased to eighty-four. America, as the country affording most facilities for systematic observations, has the leading place in the list all the way through.

Enlargement of the Sun and Moon in the Horizon.—Various hypotheses have been proposed to explain the apparent enlargement of the sun and moon in the horizon over the size they seem to present at the zenith. Experiments recently made by M. Stroobant, in Belgium, indicate that the cause of the phenomenon is a physiological one. In a darkened room, M. Stroobant had fixed to the ceiling two electric stars about eight inches apart, and on the level of his eye two similar stars, the distance between which could be varied at pleasure, while the observer's eyes were at an equal distance from either pair. When the pair of stars on the level of his eye were so adjusted as to appear at the same distance as the pair in the ceiling, they were proved on measurement to be only six and a half inches apart. He then transferred his observations to the-actual stars, selecting pairs at sensibly equal distances apart in the horizon and in the zenith, and afterward measuring their real angular separation as marked on the celestial globe. The apparent separation of the stars in the horizon was increased in almost precisely the same degree, the ratio of the real distances, which seemed to the eye to be the same, being as 100 in the zenith to from 79·5 to 81·5 in the horizon.

The Vegetation of Gutter-Stones.—Dr. Hugo Winnacker, who devoted eleven full months to the study of the subject, has published a paper on the "Vegetation of Gutter-Stones and its Relation to Infectious Diseases." The subject is one of no little importance, for, if the gutters of our streets really harbor infectious plants or germs, they are capable of being very dangerous agents for the spread of disease. Parts of them are exposed to being dried every day, and when they are in that condition the germs might be taken up by the wind and scattered everywhere, to become active whenever they are supplied with moisture. Dr. Winnacker has found that the vegetation of the gutter-stones consists of green algae and fungoids. The algæ are harmless and even beneficial, for they grow over the fungoids and at their expense, and help to keep them down. They should therefore be encouraged by not removing them, and by flushing the gutters, so as to supply them with the elements favorable to their nutrition. Most of the fungoids likewise appear to be harmless, but some of them may be dangerous, and, as it is hard to distinguish their qualities, it is well to be on the watch against them. Two of the fungoid forms, quite abundant at Göttingen, are especially described. One, a micrococcus and ferment, grows in a reddish-brown coating from early in the spring till late in the fall. Another, a mold, grows in thick masses all the year round. The character of the vegetation may be different in different cities.

Difficulties of Underground Telephony.—The difficulties in the way of at once laying the telegraph and telephone wires underground in London are succinctly stated in the "Saturday Review." The inductive effects in the telephone wires are already annoying enough, when there is room to spread the wires in the air. They would be greatly multiplied if the conductors were bunched together, as they would have to be, to be put in a tube underground. The retardative effects would also be largely increased, to a serious extent, in fact, in the case of the telephones, for they depend upon abrupt and rapid changes in the strength of the current, and these would be so far nullified as seriously to impair the clearness of the articulation if the line were of any considerable length. The expense of construction would be largely increased by the necessity of coating the wires; while the coating, mainly composed of gutta-percha, is perishable, and constantly giving rise to "faults." A system of sub-ways, like the sewers of Paris, or the underground avenues, that might be made by connecting the sidewalk vaults of New York, seems to be an indispensable prerequisite to any practicable general location of electric telegraphic and other wires under the ground. Nevertheless, the overhead electric-light wires are a nuisance, and fitly entitled to the epithet, "a Damocletian terror," which the London "Lancet" applies to them.

Food-Value of "Whole-Wheat" Flour.—Dr. Campbell Morfitt, who has been largely instrumental in introducing improved forms of bread and new methods of bread-making, has reported an experiment he has made to ascertain the relative value of common flour and of his "whole-wheat" flour. The objections to the old Graham flour, that its coarse bran was irritating to the digestive organs, were well founded. The "whole-wheat" flour is free from this fault, for the bran is not coarse or sharp-edged. Dr. Morfitt makes three kinds of flour: the crude, representing the entire grain; a standard refined granular meal, representing ninety-three or ninety-four per cent of the cleaned grain; and a pearl-white meal representing all the farina of the grain with some cerealine, about eighty-three per cent of the whole. Given weights of each of these were carefully brushed over a fine wire-cloth till all the farinaceous portions had gone through. That which was left on the sieve—called proximate bran—amounted, in the mean, to 18·28 per cent of the crude, and 12·19 per cent of the standard meal. Therefore, wheat may be said, generally, to consist of 81·72 per cent farina and 18·28 of branny matter. The proximate brans were next inclosed in fine cloths and kneaded under relays of cool water till the latter ceased to become cloudy, and by this treatment were reduced in weight rather more than one half. The residue left from this treatment was called absolute bran. It exists in a fixed ratio to the meal in all the wheats indifferently of 9·65 per cent from the crude, and 5·80 per cent from the standard meal. Thus, the total of actual bran in any wheat does not exceed ten per cent. The proximate bran was then subjected to an artificial digestive process, to discover how much more of its substance it would yield in that way. The quantity of "ultimate" bran left after this experiment was reduced by 18·44 per cent, or to 7·87 per cent for the crude meals, and by 21·88 per cent, or to 4·56 per cent for the standard meals. The more powerful natural digestion of the stomach must certainly extract still more from the meals. "Results could not be more impressive than these," says Dr. Morfitt, "as to the superior nourishing value of whole-wheat meal, for they prove that the separation and rejection of the bran must inevitably impoverish the residual farina of the flour."

Poisonous and Medicinal Herbs in India.—No country is better supplied with medicinal as well as poisonous herbs than India. The waysides and ditches abound in plants that possess some strange, and some the most deadly qualities. One of the most common of these plants is the datoora, with its large white flower, and leaves resembling those of the hollyhock. It is well known as a remedy for asthma, and its leaves are used in the shape of cigars or "tobacco," but its seeds are a subtile and powerful poison, in small quantities causing temporary insanity, and in large either permanent injury to the brain or death. The natives believe that it is used by robbers to aid them in their operations. The madār grows from two to four feet high in isolated groups along road-sides and in open, sunny places. It is soft and branching, with broad, thick, dark-green leaves covered with down, and large white waxen flowers tinged with pink toward the center. The application of the leaf is a sovereign remedy for sprains, swellings, and pains. The strangest and most powerful property of the madār resides in the milk, which exudes abundantly on the slightest scratch of its succulent leaf or stem. The natives profess to use it for any obstinate sore, especially in the nostril, but when swallowed it produces spasms of hilarious intoxication of which the patient recollects nothing after they are over. The natives say that if a probe is formed from a mixture of the madār-milk with a pounded ruttee-seed, dried and hardened in the sun, and if the skin is pricked with this and the point left, death will follow imperceptibly and painlessly in two or three days, leaving no trace of the cause but the faintest speck like a mosquito-bite where the skin was probed. The wild ganja—to which the hasheesh-plant corresponds as a cultivated species—has similar intoxicating effects, except that it is less injurious to the system. The natives chiefly use it spiced for the hookah, or as an infusion for drinking. From long continuance or excess it is a frequent cause of insanity; and this may pass away on discontinuing the use, or result in more or less permanent imbecility. It is used sometimes as a medicine for cattle. The number of herbs considered medicinal by the natives is endless. Hardly a weed grows but they find some virtue in it for some ailment or another. The large leaf of the castor-oil plant, heated and applied externally, is used for allaying local inflammation and pain. The leaf and bark of the neem-tree are similarly applied. A small weed like clover, gathered among the grass, is applied to the temples to allay headaches, or otherwise as a counter-irritant, as we use mustard. The cherita is a well-known tonic and fever preventive; and the milk of the chutwan-tree is used for stuffing what few Hindoo teeth come to be in need of that process.