Popular Science Monthly/Volume 17/October 1880/Popular Miscellany

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POPULAR MISCELLANY.

The Cotton-Worm Investigation.—The Commission for the investigation of the cotton-worm has been organized under Professor C. V. Riley as chief, and its members have been stationed at different points in the South to make local examinations. Professor J. P. Stillé, of Alabama, and Judge J. W. Jones, will represent the Commission in Texas; Professor R. W. Jones, Dr. E. H. Anderson, and Mr. Lawrence Johnson, in Mississippi; Mr. H. G. Hubbard, Detroit, Michigan, in Florida; Professor Barnard, of Cornell University, will fully study those parts of Louisiana and Mississippi which were neglected in 1878 and 1879 on account of yellow fever; Judge J. F. Bailey, and Mr. James Roane, chemist, will make a special series of experiments in Alabama; Professor J. E. Willet will make experiments in Georgia to test the usefulness of fungus-germs in the destruction of the worm. Maps are to be prepared by Professor Smith, of the State University of Alabama, showing the different cotton regions classified with reference to the hibernation of the insect. Professor Riley, besides having the general superintendence of the work, and advising with his assistants, will collect information and make other preparations for introducing the cultivation of the pyrethrum, which he believes will afford a safe antidote for the worm.

Changes in the Natural Vegetation at San Francisco.—Dr. Herman Behr has published a description of the changes that have taken place in the vegetation of the San Francisco peninsula within the last thirty years. The region was originally distinguished by three types of landscape: the sand-dunes and hills, covered with live-oak, ceanothus, horse-chestnut, and wild cherry, ferns, and common herbs; an open tract of grassy plains, with trees in the ravines, and flowering plants; and a marshy plain, with boggy prairie, covered with a varied growth of bushes and herbaceous plants. Now, the first mentioned type of vegetation, the chaparral, exists still in a few spots; the second, that of the pasture-land, is to be met with still, wherever the distance from the city is considerable enough to protect native vegetation; but the third type has entirely disappeared. In the course of the extension of the city, Australian evergreens and conifers form the Sierra have largely replaced the original trees. "Parallel with this artificial immigration of Australian arborescents, goes on an herbaceous immigration from Europe and Africa." The thistle (Silybum marianum of the Mediterranean region) has invaded both California and South Australia, and, wherever it gets a hold of the soil, all native vegetation disappears. The tree-lupines particularly suffer from its encroachment. Another weed, Cotula coronopifolia, a native of South Africa, well known in Mediterranean Europe, and which has invaded South Australia, does the same work in moist ground that is begun by silybum in more arid tracts. It "has transformed the varied aquatic vegetation of the different places infested by itself into one monotonous green mass with yellow buttons." Dr. Behr regards as significant that these two plants are congenital and belong to one of the most modern orders, of which fossil specimens are found in only the most recent formations, and to which he attributes the vigor of youth.

The Physiological Effects of Tea and Coffee.—Professor Albert B. Prescott, M.D., of the University of Michigan, has published a paper, in "The Physician and Surgeon," on the physiological effects of coffee as compared with those of tea, concerning which the authorities are confusing and little is really known. Inasmuch as the chief constituents of both substances are capable of determination, we ought to be able to declare something, he thinks, as to what there is in common between a medium cup of coffee and an average cup of tea. The effects of tea and coffee, he continues, must be mainly due to the properties and proportions of the alkaloids, tannin, volatile oils, and ordinary food-substances contained in them. As to the alkaloids, no differences have been established between theine and caffeine. In average quantity, the alkaloid forms about one per cent, of the raw coffee-berry, and two or three per cent. of tea. A little of it, but very little, is lost in roasting coffee. The greater part of it is extracted in the beverage as usually prepared, both of tea and coffee. A pound of tea usually furnishes from three to five times as many pints of beverage as are obtained from a pound of coffee, but the ways of preparing and the estimates are so different that nothing exact can be determined on this point. As a whole, the proportions for given volumes of beverage can not be declared habitually much larger in the one than in the other; if there is any difference, the coffee-beverage is likely to be the stronger. The tannins are tannic acid in both substances—boheic and gallic acid in tea, and caffeic acid in coffee, all astringents. Tea contains, according to the analyses relied upon by Dr. Prescott, from six to twenty per cent., an average of twelve per cent, of tannins; some other estimates make the percentage very much larger. This large amount is, however, by no means all dissolved in the ordinary preparation of tea as a beverage. No tannin was dissolved in steeping for five minutes six out of eleven specimens of different qualities of tea at the Michigan University, and the percentage of the other five specimens was not large, the average percentage of the whole being only 0·08. After thirty minutes' steeping, the quantity of tannin dissolved varied from 1·09 to 4·50 per cent., the average being 2·49, and was in no case equal to half the amount contained in the tea. A larger quantity of tannin was extracted in other experiments in which the tea had been macerated at ordinary temperature before boiling. The tannin in coffee-berry, by all reports, is not more than one third the quantity of that in tea-leaves, and may be considerably less. Six specimens of coffee were steeped for five minutes without yielding any tannin; two of them showed a trace of tannin after ten minutes' steeping; after twenty minutes', five of the specimens showed from 0·01 to 0·25; after thirty minutes', the proportion of tannin given up varied from 0·09 to 1·80, the average being 0·83. Other analyses show that tea contains an average of 0·206 grains, coffee 0·055 grains, of tannin to the fluid ounce of the beverage in use. These results leave no doubt that the tea we drink contains at least four or five times as much tannin as the coffee we drink, and that the tea yields only a small proportion of its large quantity of tannin, after from five to ten minutes of steeping. If tea or coffee is to be administered, as in any case of poisoning by alkaloids, tea, well steeped, is to be chosen as the better antidote for the precipitation of alkaloids, and equally potent as a stimulant. The essential oil of tea is a very small but distinct constituent, the most important factor in determining its market value. It is conjectured to be an organic stimulant, and may promote perspiration. Coffee, in the unroasted berry, has no volatile oil; but, in roasting, an agreeable essential oil is developed, the effects of which are not known, but which may cause the digestive disturbance sometimes ascribed to coffee-drinking. Of nutrient substances, tea contains pectin, gum, legumine, and indeterminate matters, yielding, in all, to boiling water about thirty-two per cent, of its weight. Coffee contains, after roasting, from one to two per cent, of glucose, ten to twelve per cent, of fat, nearly as much legumine, and a little gum, and yields thirty-five per cent, to water. "It is not unlikely," Dr. Prescott concludes, "that these food-substances, as modified by roasting, disagree with the digestion of many persons. This is, let me submit, a not improbable explanation of the class of injurious effects of coffee-drinking, when the substitution of tea-drinking gives relief. The powerful nerve-stimulant, caffeine, as we have seen, is obtained in about as large doses from tea as from coffee. The caffeine of both these beverages undoubtedly produces injury to the nervous system in many cases; but, when coffee causes palpitation, sleeplessness, etc., not resulting from tea, let me suggest that some attention be paid to the digestive organs."

Water in Disease.—Dr. S. G. Webber, in the "Archives of Medicine" for August, attributes a considerable value to water as a preventive and a remedy of disease, and opposes the abstinence from drinking at meals, advocated by many, as injurious. Among patients who have come under Dr. Webber's care affected with "symptoms of an undefined character, a vague unrest and disquiet showing itself by discomfort or even pain, sometimes in one place, sometimes in another," with constipation and an unhealthy hue of the skin, he has found that many were accustomed to take less than the usual average quantity of drink. In such cases he would prescribe an increased quantity of drink, with beneficial effects in increased perspiration, and the decrease or disappearance of the unpleasant symptoms. The waste of tissue-changes in the system passes into the blood, and leaves the system only in solution. This, Dr. Webber maintains, can not take place unless enough water is taken. Further, "water taken with the food favors digestion; when taken into the stomach a part is absorbed by the gastric vessels, carrying with it the soluble constituents of the food. So much as is not immediately absorbed assists in softening and breaking up the larger particles of food, and thus aids in the gastric digestion by facilitating the action of the gastric fluids." It also makes it easier to keep the bowels regular. In estimating the quantity of water to be taken daily, we should remember that water is excreted by the lungs and skin, as well as by the kidneys, and that much food contains water. Hence the amount required must vary slightly with the activity of the skin and the character of the food. Dalton states that the average amount is about fifty-two ounces, or 3·38 pints, or the equivalent of eight or nine coffee-cups of drink.

Temperature of the Breath.—Mr. R. E. Dudgeon has been trying some experiments on the temperature of the breath, and infers from the results that it is considerably higher than has generally been stated, and that it is variable. First, on rising in the morning, having ascertained the temperature of his body as shown by the thermometer in the axilla and mouth to be normal—about 9812° he wrapped the thermometer tightly in a silk handkerchief and breathed upon it. In five minutes it indicated 106·2. At 7 p. m., after a brief walking exercise, and when he had eaten nothing but a spoonful of boiled rice, and drunk only half a glass of water and a mouthful of ginger beer, his breath raised the mercury to 107°. Immediately after a dinner at which only water was drunk, a temperature of 108° was shown. At other times the thermometer would not rise, under apparently the same conditions, higher than 102° to 105°. He can suggest no way of accounting for these indications otherwise than by admitting that they show the actual temperature of the breath as it issues from the lungs. "If so," says Mr. Dudgeon, "it is by the breath that the system gets rid of its superfluous caloric." The experiments seem to show that the temperature obtained from the breath is higher when the surrounding air is warm than when it is cold, indicating possibly that more heat is passed off by the breath when less can escape from the general surface of the body.

The Ancient Outlet of Lake Bonneville.—The name of "Lake Bonneville" has been applied to a great body of water which formerly covered the desert basins of Utah, of which the most conspicuous vestiges are its shore-lines. It is known from them that the ancient water-surface was more than ten times as great as that of the Great Salt Lake, and that the ancient level of the water was about one thousand feet above the modern level. The point at which the waters of this lake were discharged is still undetermined. Mr. G. K. Gilbert maintained, in the "American Journal of Science" for April, 1878, that the point of overflow was Red Rock Pass, Idaho, at the north end of Cache Valley; that the discharging stream descended through Marsh Valley, and thence continuously to the Pacific Ocean; and that, flowing over soft material at first, it gradually excavated at the pass a channel more than three hundred feet deep, and lowered the level of the lake by the same amount. Dr. A. C. Peale controverted Mr. Gilbert's conclusion in a subsequent number of the "Journal," and held that the original altitude of the Red Rock Pass was considerably below the highest level of Lake Bonneville; that the original shore-line exists in Marsh Valley, at the north end of the pass, as it does in Cache Valley at the south; and that the real point of discharge, when the water stood at the Bonneville level, was about forty-five miles north of Red Rock Pass. Mr. Gilbert has, within a few months, revisited Marsh Valley and Red Rock Pass, and other points near the former supposed outlet of the lake, and gives in the May number of the "Journal" his reasons, derived from his later observations, for adhering to his former conclusion. He assumes to determine the character of the body of water which has occupied a given spot, whether it was a stream or a lake, from the nature of the terraces left in the valley. Thus there are stream terraces, and wave-terraces, and delta-terraces, and others, all marked by distinct features. A lake should leave wave-terraces or delta-terraces. In revisiting Marsh Valley, he traversed it from end to end, making a careful search for the terraces of the ancient shores, selecting the most favorable stations and lights he could get. He saw stream-terraces and displacement-terraces of considerable magnitude, and a few inconspicuous terraces due to unequal erosion, but no wave-terrace and no delta-terrace. He made a special examination of two terraces referred to by Dr. Peale in support of his views, but did not recognize in them any features inconsistent with the opinion that they are stream-terraces. He consents to reconsider his original location of the outlet of the lake at the time of the beginning of the overflow, and assigns it to a position two miles north of Red Rock, instead of at that point, and the distance nearer to the place fixed by Dr. Peale than the place where he first fixed it. Mr. Gilbert Thompson, an expert topographer, visited the northern limits of the lake in 1877, while ignorant of the results of Mr. Gilbert's examination, and came to the same conclusion that he had reached. In a letter to Mr. Gilbert, dated April 10, 1878, he says: "I was delighted, at Red Rock, to see unmistakable evidences of the ancient outlet of Great Salt Lake. . . . Thus you may have the gratification of knowing of an independent and entirely unbiased verification of your determination of this point."

A Fresh-water Medusa.—A new medusa, which lives in fresh water—the first freshwater medusa known—has been discovered in the tank of the water-lily house of the Royal Botanical Society in London. It flourishes and multiplies rapidly in water of a temperature of about 90°, and the specimens with which the tank swarms are described as being very energetic in their movements and apparently in the conditions which contribute most completely to their well-being. The new jelly-fish has attracted great attention among naturalists, and minute descriptions of it are given by Mr. Romanes and Drs. Allman and E. Ray Lankester. Mr. Romanes has found that exposure to sea-water kills it, and that it is more intolerant of sea-water than are the marine medusas of fresh water. Dr. Allman has named it Limnocodium Victoria and gives it a position between the Leptomedusæ and the Trachomedusæ, while he regards its affinity with the Leptomedusæ as the closer.

Origin of Chinese Civilization.—A new view of Chinese civilization has been presented by M. A. Terrien de la Couperie, who asserts that the ordinary opinion, which would regard China as a world by itself—with a distinct language, and a peculiar way of writing which it has invented for itself—is incorrect, and is based on insufficient study. The error has been committed by regarding the Chinese and their language as they are, and not studying them historically and tracing them as far back as possible. This M. Terrien de la Couperie has done, according to the testimony of Professor Robert K. Douglas, with success. Great changes were made in the language in the early centuries of the Christian era, and the present system dates from no further back than the fourth century. The more ancient language may be studied from a number of sources, of which M. Terrien specifies eleven classes. One of the most important documents is the Yh King, which is supposed to embody some of the most ancient writings in the language. Some of the texts are attributed to the times of the legendary Fuhhe, b. c. 2852, and became the subject of commentaries as early as b. c. 1150. M. Terrien is the first person in modern times who has succeeded in explaining any of it. The archaic Chinese characters were derived from hieroglyphics, and the hieroglyphics were accompanied by a certain number of phonetic signs. A study of the most ancient forms and a comparison with the other sources of information have led M. Terrien to recognize in the Chinese spoken language an ancient member of the Ural-Altaic family of agglutinant languages, in which it constitutes a new, a third division of the Amardian group, a group which also includes the Akkadian and its dialect, the Susian and Kossian languages. The vocabulary of the ancient language, as may be shown by citations of hundreds of words, connects it with the Akkadian and Susian dialects; but it has certain "very marked grammatical affinities" with the Ugro-Finnish tongues. The resemblances of the ancient Chaldean and Chinese hieroglyphics are very strong; and one point to be noticed is that, in both systems, the images are drawn full-face instead of in profile, as in Egyptian hieroglyphics. Further evidence of the connection thus suggested is given in the facts that certain parts of the Yh King are only lists of meanings that pointedly recall the Akkadian cuneiform syllabaries; that Hoang-ti, the first of the five Chinese emperors who reigned at the dawn of history, was in the ancient language Nak-kon-ti, suggesting a correspondence with the Susian god Nakhunta and King Kudur Nakhuta; and in numerous cases of at least apparent correspondence in the most ancient titles, customs, and allusions of the Chinese and the Susians. Resemblances have also been pointed out between many Western features and those of the Chinese. A part of these, M. Terrien admits, is owing to the progress of the Chinese, to communication, and later changes; but another part, he maintains, "perhaps the earliest and most important, traces its origin to the first establishment in ancient China of a part of that Akkado-Chaldean culture, to which our modern civilizations are indirectly so referable."

Curious Discovery of a Murder.—A story of a remarkable discovery of a murder comes from Bermuda. A handsome and decent mulatto woman suddenly disappeared in October, 1878, and her husband was suspected of having murdered her, but no trace of her could be found, and it seemed probable that the crime would not be detected. A week afterward, while anxiety on the subject was still at its height, some boatmen, looking out toward the sea, were struck by observing in the Long Bay Channel, the surface of which was ruffled by a slight breeze, a long streak of calm, such as a cask of oil usually diffuses around it when in the water. A connection with the disappearance of the woman was at once suggested; a search was shortly afterward made at the place for the body; the skeleton was found held down by weights, and the fragments of flesh remaining upon it were in such a condition as to show that it had not lain long in the water. Identification was established by means of portions of clothing. The man, who was a fisherman, had calculated that the fish, which were numerous in the channel, would soon destroy all means of identification of the body, but it never occurred to him that their ravages as they did so would set free the matter which was to write the traces of his crime upon the surface water. The peculiar feature of the calm seems to be a novel one, not mentioned in works on medical jurisprudence and outside the experience of doctors.

The Climate and Meteorology of Zanzibar.—Considerable interest is attached to the climate and meteorology of Zanzibar, since that island is the starting-point of most of the expeditions which proceed into the interior of East Africa. Observations taken by Dr. John Robb, of the Indian army, during the five years from 1874 to 1878, show that the average rainfall, which they give at not more than sixty-one inches, or double that of England, has very materially decreased since the-time when Dr. Christie and Captain Burton made their observations; and it is suggested that the decrease may be due to the destruction of the trees over the whole island by a cyclone which swept it in 1872. The average number of rainy days is one hundred and twenty in the year. The double seasons, which are of unequal duration, are marked out by the prevailing winds, and are less exactly determined by the so-called greater and lesser rains. The rainy seasons begin when the sun crosses the zenith of Zanzibar in passing to its northern and southern declinations, March 4th and October 9th. The greater rains fall in March, April, and May, the lesser rains from the middle of October to the end of the year. The driest month is September. The mean temperature of the five years was 80·6°, the hottest months being February and March, with a mean temperature of 83·1° and 80·4° respectively, the cooler are July and August, with mean temperatures of 77·5° and 77·7°. These figures give a variation of less than 6° in a year, and to this limited range is ascribed the debilitating nature of the climate. The mean pressure of the barometer for four years differed but a thousandth of an inch from that indicated at the equator. The coast of the mainland of Africa, Dr. Robb says, is undoubtedly prejudicial to health, and both Europeans and natives of India who pass any considerable time there suffer severely from fever of a bad remittent type, and from dysentery. All seasons are bad, but some are better than others, and travelers going into the interior are usually advised to leave the coast-region before the heavy rains begin to fall. The seeds of disease are often sown by even a short residence on the coast, and the traveler dies before he has advanced many marches into the interior. Travelers, therefore, should always make a careful and quick march across the unhealthy belt of country along the coast, and pitch their camps in the higher and drier districts beyond; and, if they have to linger on the coast, they should take care to pass their nights in the safest places they can find.

Application of Cold in Industrial Chemistry.—Heat, of temperatures above the freezing-point of water, has long been known and used as one of the most powerful agents for producing the chemical operations desired by manufacturers. Heat of temperatures below the freezing-point, or cold, as it is commonly called, has been less generally employed, and enjoys less recognition as a force capable of practical application for production. It has been lately made to aid in the manufacture of Glauber's salt at some French works with such success as to suggest that its more general application is possible in other directions. Alum and copperas were formerly made from the pyretic shales of Rheims and Picardy, but the product from these sources has been driven from the market by the competition of other alums. A new process has been devised by M. Georges Fournier, of Paris, under which the lye from the oxidized shales, containing all of the aluminum sulphate and a portion of iron sulphate after a considerable part of the copperas has been deposited, is mixed with common salt in such proportion that there shall be sodium enough to combine with all the sulphuric acid, and chlorine enough to take up all the aluminum and iron. The mixed solution is then exposed to a temperature of from 3° to 5° below the freezing point, at which the sulphate of soda is almost insoluble. That substance is deposited in the ordinary form of Glauber's salts as a fine crystalline sediment, while the aluminum and iron remain in solution as chlorides. The "mother-liquor," or lye, is then run off, and the deposit is washed in brine cooled down to the freezing-point. After it is dried, it is fit for any purpose to which Glauber's salt is applicable. The mother-liquid which has been run off may be made into a chloride of aluminum, which is valuable for disinfecting purposes. A pure chloride of aluminum, suitable for use in dyeing, and for the destruction of the vegetable matter which is mingled with wool, may be prepared from cake-alum by a similar cold process. The results of the operation are, as before, a deposit of Glauber's salt and a solution of chloride of aluminum, but the latter substance is free from the admixture of iron. Another French inventor, by exposing the lyes of the "sal mixte" of the salt-works of the Mediterranean coast, consisting of common salt and sulphate of magnesia, to a temperature of about 11° below the freezing-point, obtains Glauber's salt in deposit with a solution of the chloride of magnesium, a substance largely used for weighting textile fabrics.

Fertility of Hybrids.—Mr. Darwin, in his "Origin of Species," has mentioned a case on the authority of Mr. Eyton, in which hybrids from the common goose and the Chinese goose were as fertile as among themselves. He has now reported in "Nature" concerning his success in raising birds from the eggs of a brother and sister from the same hatch of hybrids of these two species. Two trials were made: three birds were hatched from the first set of eggs, two others were fully formed but did not succeed in breaking through the shell, and the remaining eggs were unfertilized. From the second lot of eggs two birds were hatched. The hybrids, grandchildren of the pure parents, were extremely fine birds, and resembled their hybrid parents in every detail. Mr. Darwin's success was not equal to that of Mr. Eyton, who reared eight hybrids from one set of eggs; and he attributes the difference in part to the close confinement in which the hybrid parents were kept and their close relationship. Another illustration of the possible fertility of hybrids to which attention has been directed, is given in Mr. J. A. Allen's "History of the American Bison," where it is said that that animal interbreeds freely with the domestic cow, and that the half-breeds are fertile.

The Highest Mountains of the Earth.—Hermann von Sclagintweit Sakünlinski, in the last volume of his journeys in India and high Asia, gives a table of altitudes, including statements of the heights of the most elevated mountains. The elevations are not extraordinary south of the Himalayas, the most marked ones being four mountains from 11,000 to 15,300 feet high in Assam, and the Sufed Koh peak in the Punjaub, 19,839 feet high. The eastern Himalayan district, embracing Bhootan, Sikkim, and Nepaul, contains the highest mountain known on the earth, which is called Mount Everest by the British, Gaurisankar by the people there, and is 29,002 feet high; and the third highest, Kintchinjunga, 28,156 feet high, and has besides thirty-two mountains of more than 20,000 feet, and thirty-two of more than 10,000 feet. The western Himalaya region, extending from Kumaon to Hazasa, exhibits the Nanda Devi in Kumaon, 25,749 feet, as its highest peak, and has besides twenty-nine mountains of more than 20,000 and 108 of more than 10,000 feet in height. In eastern Thibet are ten Alpine stations between Lassa and Guari Khorsum, more than 10,000 feet high, two of them reaching to 15,500 and 16,700 feet, and Lassa, the capital, is 11,700 feet high. Western Thibet, from Guari Khorsum to Balti, ranks next after the eastern Himalayan region in its elevations, having within its boundaries the second highest mountain known on the earth, the Dapsaug, 28,278 feet high, with twelve mountains of more than 20,000 and seventy-three of more than 10,000 feet in height. The highest point in eastern Turkistan is the summit of the Kwen-lun, 20,000 feet high. The great passes of the world are in this territory. They include the Kizilkonira pass in Yarkand, at an elevation of 17,762 feet, the Kilian pass in Khotan, 17,200 feet, and the Elchi-Davan pass in the Kwen-lun Mountains. The snow-line appears at a height of 15,100 feet on the north side of the Kwenlun, of 15,800 feet on the south side, of 18,665 feet on the western slopes of the Guari Khorsum, and 18,010 on the northern slopes; and phanerogamous plants reach up to 19,237 feet on the western side. The highest places inhabited by man are in Thibet at a height of between 14,800 and 15,000 feet, but above these are the Hanli Cloister, 15,117 feet, and the Thok Jalang gold-field, 16,330 feet. In all, these mountain regions contain seventy-three peaks more than 20,000 feet high, of which seventeen rise above 25,000 feet. Dhawalagiri, in Nepaul, 26,680 feet high, which was formerly considered the highest mountain on the earth, is remanded to the fifth place, being exceeded, besides the three already named as the three highest, by the Sisbut peak, in Nepaul, 27,799 feet.

Butter-making in Denmark and Sweden.—Some of the best butter in Europe is made in Denmark and Sweden, and commands a price in the London market 23 per cent, higher than the best Cork butter. Canon Bagot, who has taken pains to investigate this subject, ascribes this superiority to the education of the dairy-maids, which has been systematically pursued in Denmark since 1864 and 1865. In Sweden the dairy-maids are sent to a college and educated in dairy management for six months, at the end of which time they receive certificates and are considered competent to work in large dairies. Their instructions are very definite as to every feature of the operation of butter-making, including the quality of the salt and the coloring matter, and the food of the cattle; the quality of the butter is consequently uniform. A part of a lot of Cork butter may sometimes be sent back by the wholesale dealer because it is not equal to the rest, but this is said never to happen with Danish butter. The selection of the cows and the feeding of them are the first important points in the business. The Danish dairymen keep their cows tethered during the summer in "splendid clover and rye grass," and feed them in winter exclusively with clover hay, linseed-cake, and rape-cake. The milk is set in such a way that the cream shall be got off while it is still perfectly sweet, for they will not churn it if it is in any other condition. The proper temperature for churning, which is from 57° to 60°, is essential, and the churning should not be continued too long. The best butter-makers stop churning at the very moment the butter appears in the form of grains like shot. They pass off the buttermilk through a strainer, then put the butter back with water, give it a few more turns in the churn, strain again, and repeat the operation till the water runs off as clear and bright as when it is put in. Salt is added by weight, at the rate of six pounds of salt to a hundred-weight of butter, by being sprinkled over the butter after it has been spread out in layers; a few turns are given the mass with the butter-worker, and the process is complete.

Diffusion of Bacteria.—M. Miguel has learned from his investigations of bacteria and germs in the atmosphere that the number of bacteria, which is small in the winter, increases through the spring, and becomes large in the summer and fall, then diminishes again during the months of frost. The same is the case with the spores of fungi; but while the molds are abundant during moist periods, the number of aërial bacteria then becomes very small, and does not increase again till the soil has been dried, precisely when the fungoid spores are rare; so that the maxima of mold-microbes and the minima of bacteria-microbes correspond with each other, and vice versa. While in the summer and fall a thousand germs of bacteria may often be found in a cubic metre of air, in winter the number falls to four or five, and on some days the dust from two hundred litres of air is incapable of causing the infection of the most alterable liquors. Usually, in M. Miguel's laboratory, the dust of five litres is enough to cause infection, and in the sewers of Paris the particles in one litre will do it. A comparison of the number of deaths in Paris from infectious diseases with the number of bacteria present in the atmosphere showed that every increase of bacteria in the air was followed in about eight days by an increase of the deaths in question. M. Miguel further represents that he has found that the water vapor which rises from the ground, from rivers, and from masses in full putrefaction, is always micrographically pure, that gases from buried matter in the course of decomposition are always exempt from bacteria, and that even impure air sent through putrefied meat is purified under certain conditions.

The Thread-Worm of the Dog.—The cruel thread-worm (Filaria immitis) of the dog was described thirty years ago in the "Proceedings" of the Academy of Natural Sciences of Philadelphia, and has since been repeatedly noticed as infecting dogs in Europe, India, China, Japan, and this country. The heart of a dog, with the ventricles stuffed with the worms, is preserved in the Museum of the University of Pennsylvania. A specimen of the heart and part of one lung of a dog containing the worms has recently been sent to the Academy of Natural Sciences, by Mrs. Laura M. Towne, of Beaufort, South Carolina, who has also furnished a description of the symptoms shown by dogs afflicted with the parasite. She had lost several dogs, and a gentleman living on a neighboring island had lost more than thirty hunting-dogs in two or three years with the same symptoms. The most characteristic symptom appears to be a peculiar cough, which is excited by any movement, especially after sleeping, ending in a violent effort to bring something from the throat, but nothing is thrown up. When they began to run violently, the afflicted dogs would fall down and become stiff and insensible, but would in a short time get up and renew the chase. A large Newfoundland dog grew ill, exhibiting the drowsiness, lassitude, and inclination to turn round and round when he attempted to go anywhere, which marks the conduct of sick dogs, and finally became subject to spasms. He was examined after death, when one filaria was found lying at full length in the windpipe, and others were found stretched at length and crowded closely in the large artery. Upon cutting into the heart, the worms burst forth in bunches, slowly uncoiling themselves. They were white, stiff, and wire-like, and not at all stained with blood. The large blood-vessels of the lungs were filled densely, and large filariæ were withdrawn with some difficulty even from the small ones. The worms lived in water about twenty-four hours.

Production of Artificial Diamonds.—Mr. Hannay lately gave an account to the Royal Society of his experiments in producing artificial diamonds. As far back as the fall of 1879, he was searching for a solvent of the alkali metals, and tried many experiments with different liquids and gases, with the invariable result that, when the solvent reached the permanently gaseous state, chemical action ensued. A number of experiments were made with sodium, potassium, and lithium, and the hydrocarbons, but the metals almost invariably combined with the hydrogen, setting the carbon free. A series of experiments made with sodium and paraffine-spirit gave a deposit of very hard scales of carbon. This was the reaction upon which the experiments for obtaining crystalline carbon were built. From his experiments in solution, Mr. Hannay concluded that the solvent power of water was determined by two conditions: first, temperature, or molecular vis viva; and, second, closeness of the molecules on pressure, which seems to give penetrative power. It should follow, then, that, if one body has a solvent action upon another without acting upon it chemically, such solvent action may be indefinitely increased by increasing the temperature and pressure of the solvent. Out of more than eighty experiments which Mr. Hannay made for producing crystallized carbon, only three were attended by results of a satisfactory nature. The first experiments were made with sodium and paraffine-spirit, in tubes of hydraulic iron, twenty inches long, an inch thick, and of a half-inch bore, three parts filled. The tubes, fitted with screwed plugs, nearly all leaked, and had to be welded up. Then one exploded before it became visibly red, another showed a deposit of scaly carbon, and a third gave out a strong jet of gas when opened, while the iron appeared to have been converted to steel. Concluding that diamonds were not likely to be obtained by that means, Mr. Hannay returned to the idea of dissolving carbon in a gaseous menstruum. A distillation from bone-oil containing nitrogenous bases seemed to him the most likely substance to yield the solvent. It was placed in a strong tube with charcoal, and heated for fourteen hours. The gas rushed out with force on opening the tube, and a few bright particles of carbon appeared, differing but little, however, from particles of wood-charcoal. Another experiment was made with lithium and a mixture of highly rectified bone-oil and paraffine-spirit, placed in a tube twenty inches by four inches, with a bore of half an inch. This was heated for fourteen hours, then cooled slowly. On opening it, after the outrush of gas a little liquid was found, and at the upper end of the tube as it lay in the furnace, a hard, smooth mass, which was removed with a chisel. Some hard particles were found in pulverizing this mass, which, on examination, proved to be transparent crystals of carbon, or diamonds. New experiments were made with other alkali metals, paraffine-spirit, and bone-oil, but they yielded nothing except the scaly carbon. Even the lithium did not act in the same manner as before. This metal having, however, given the best results, Mr. Hannay determined to use it in his further experiments, but was troubled by frequent disasters and explosions, although he again got, in one of the trials, a small quantity of carbon crystals. A curious fact that has been brought out by the examination of the crystallized carbon that was obtained is that nitrogen was present in chemical combination with the carbon. Mr. Hannay is inclined, therefore, to believe that his diamonds were formed by the decomposition of a nitrogenous body, and not by the decomposition of the hydrocarbon. The diamonds, moreover, were not found when nitrogen was absent; but the successful experiments are still too few, and the evidence too vague, to justify drawing any conclusions on this subject.

The Nile and its Ancient Channels.—M. Delamotte, who has made himself well acquainted with the geology and geography of Egypt, has published the opinion that, besides the Nile, that country was watered in prehistoric times by rivers that ran through the present dry sand-channels which the Arabs call Bahr-et-Abied, or rivers without water. The fact that river-shells were discovered in these beds during the French expedition to Egypt lends some support to this view. M. Delamotte has devoted some twenty years to the examination of the subject, and, while he does not undertake to determine when the rivers were dried up, he has reached a conclusion as to the manner in which it was done. He believes that the whole plateau of Khartoum was in prehistoric times a grand lake whence the Nile issued as it now issues from the Victoria and Albert Nyanzas. The cataracts were, however, higher than they are now, and the river, instead of precipitating the whole mass of its waters over the rocks, was divided into streams which found their way through the channels marked by the present Bahr-et-Abiad, and carried the water into the parts of the country which are now desert. The granite and porphyry of the cataract were gradually worn away in the course of ages, their level was lowered, and the Nile, instead of being forced into branch-channels, fell over them and concentrated its waters into its present single stream. M. Delamotte is examining the region of the Upper Nile again, for the purpose of verifying his theory, and of determining if it is possible, by constructing a system of dams and sluices, to raise the level of the cataracts, and cause the waters to flow again through the channels they have deserted.

Sports in the Colors of Squirrels.—A correspondent of "Forest and Stream" relates an interesting instance of the development of varieties of colors in squirrels, which took place in South Carolina several years ago. A Mr. K——, who owned a considerable plantation in the county of Marlborough, had presented to him a pair of milk-white squirrels. His woods were much frequented by gray squirrels, and fox and black squirrels were numerous in the pines and cypress-swamps at some distance from the plantation. The white squirrels bred, producing two young ones, also milk white. The animals were very prolific, under the protection of the owner, who prohibited the intrusion of hunters, and, in course of time, spread to the adjoining plantations, and many of them took to the immense swamps "bordering on the Big Peedee River. They also began to sport and change their color, and, from being pure white, became marked with every possible variation of black and white. The correspondent who relates these facts has killed, at various times, at least a dozen thus marked. One of them was of a deep, sparkling black color, except as to the ears and the large, bushy tail, which were snow-white, save a small commingling of the black and white at the root of the tail, and the lower part of the belly and the inner edge of the flanks, which were of a clear ash-gray. The varieties seem to have almost disappeared since the war. In the last individual that the correspondent has noticed, the markings were less pretty and the colors less distinct; the white was turning to ash and the black to brown, the consequence, he supposes, of wild breeding.

A New African Tribe.—Dr. Emil Halub recently addressed the London Geographical Society respecting a hitherto undescribed African tribe called the Marutse. They inhabit the country formerly ruled by the Makololo, described by Dr. Livingstone, who have ceased to exist. Dr. Halub said that when he crossed the Zambesi, and entered into their country, it seemed that he had left Africa, for the tribes were entirely different from the others in South Africa. They belong to the Banti family, but differ from the other members of this family in their appearance, customs, and workmanship. They have their own civilization, independent of influence from white men; and, while the other tribes have nothing which could be called a religion, they believe in a Supreme Being and in a life after death. They call the Supreme Being N'yambe, but have so great a reverence for him that they do not like to pronounce his name. Whenever a serious event happens, as when a man is killed by a buffalo, a crocodile, or an elephant, the common expression is "N'yambe has ordered it, and it is no use resisting." When a member of the royal family was ill, he was taken to the grave of one of his ancestors, when the king knelt on the grave, and prayed to the deceased, "You, my grandfather, who are near to N'yambe, pray to N'yambe that the disease may be taken from this man." When a great disaster happened, as in the case of the river over-flowing its banks, the people gathered around the graves of the chiefs, and prayed, "You, who are with N'yambi, pray for us." Previous to the present reign, the king was assisted by a Great Council and a Privy Council, and the cases of persons who were thought to be guilty of crimes deserving capital punishment were submitted to the Great Council for decision. The present king has abolished this usage. This king assumed to have supernatural powers, and the people believed in his pretensions and were afraid of him; but he attempted at one time to exercise his powers publicly to secure the return of some chiefs whom he had condemned to death and who had run away, and failing, lost his reputation. The people are superior to all the South African tribes in the character of their clothing, their skill in working in ivory and metals, and their customs generally. They trade with the other tribes to the north and to the west. They excel the more southern tribes in mental ability, cultivate music, and hold women in high esteem.

Hygienic Conditions of School-Life.—The "Lancet" has undertaken to inquire into the hygienic conditions of school-life in educational establishments, including those in which only the most limited numbers of pupils are taken. Aiming principally to disclose defects which are generally over-looked or little noticed, it invites and expects the coöperation of the conductors of the schools. It has framed a list of questions relating to the character and capacity of the premises, their original purposes and their adaptation to the uses of a school, the accommodations for pupils, provision of air and diet, the hours of school work and the time given wholly to play, the general health of the establishment, and the amount of illness during the year, the appearance or non-appearance of epidemic disease, the sanitary arrangements proper of the establishment, the provisions for isolation in case of a sudden attack of infectious disease, and the system of medical inspection which may be in use. The results of its inquiries as a whole will be given in the form of reports and suggestions with a view of defining, so far as may seem expedient, the conditions of health in body and mind of youth attending school.