Popular Science Monthly/Volume 21/June 1882/Popular Miscellany

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Sewerage of Large Villages.—Mr. James T. Gardiner, Director of the New York State Survey, has made a valuable report to the New York State Board of Health on the methods of sewerage for cities and large villages. He finds, after inquiry, that where, in general, intelligent efforts have been made to produce proper sanitary conditions for towns, cess-pools and vaults have been abolished, and the sewage is removed from the neighborhood of dwelling-houses by dry removal, or by water-carriage or sewerage. The efficiency of the system of removal by means of the dry earth-closet depends upon constant proper attention. In practice, it is found that the provision of fine, dry earth, and the constant intelligent surveillance necessary, can not be secured from any but exceptional families. The system can not, therefore, be safely recommended for towns in which a large proportion of the people are always ignorant and careless. The tub, cask, or pail system, which is used even on a large scale in England, France, and Germany, "is undoubtedly the best method of removal, where towns have neither water supply nor sewerage." In this system, the refuse matter is allowed to fall into a tub or cask, which is removed, emptied, cleaned, and disinfected by the town authorities at least once a week. At Manchester, England, sifted ashes are added during use to the contents of the tub, as a deodorizer. This system is successfully employed at Manchester and Rochdale, England, at an expense of $95 per thousand persons, or ten cents per person per annum; and is recommended for villages which can have no general water-supply. The weakness of it is, that the removal, cleansing, and disinfecting of the tubs require constant care and expense, and may be neglected by careless, ignorant, or parsimonious village authorities—a weakness rather attributable to village authorities than to the system—but under no circumstances could the evils of such neglect be comparable with those of privy vaults. The system is, however, unavoidably inferior to that of sewerage, in that it does not provide for the removal of wastewater and slops. Mr. Gardiner expresses a decided preference for the "separate" system of sewerage, which is adapted to carry off slops alone, to the "combined" system, in which the attempt is made to carry off both slops and storm-water by means of one set of conduits. He regards the separate system as vastly cheaper than the combined, and as very much more wholesome, in that it does not supply the territory for the cultivation of the bacteria that find rich and extensive propagating grounds on the moist, unglazed walls of the large combined sewers. A conspicuous example of the successful application of the separate system is found at Memphis, Tennessee.

Origin of the Son's Light and Heat.—Dr. H. R. Rogers, of Dunkirk, New York, has come forward with a criticism of the existing theories of the origin of the light and heat of the sun from combustion, mechanical action, or shrinkage of the sun's mass, as insufficient and not adequately supported by the analogies of any facts with which we are acquainted, and has advanced a theory that they are the result of electrical action. The sun, he believes, is a cold body, like the earth, but so constituted and so situated relatively to the earth that a stream of electric currents is constantly passing between the sun and the earth. These currents reach their points of greatest intensity within our atmosphere, where all the manifestations of force which we assign to the sun's surface really take place. Dr. Rogers also believes that the phenomena of gravitation may be traced to the same origin.

The Germination and Vitality of Seeds.—Dr. Richard E. Kunze, has collected a number of facts respecting the germination and vitality of seeds, in an essay which was read by him before the Torrey Botanical Club last December. Some seeds, to grow, must be planted immediately on maturity. Familiar examples are those of the elm and maple, the oak, and most of our common nuts. The seeds of the larkspur (Delphinium formosum), of some gentians, and of Angelica, partake of this character. Spanish chestnuts and filberts, however, have been sent, enveloped in wax, to the Himalayas, and plants from them are now growing there. Seeds of the Victoria regia had to be transmitted from America to England in water before the first plant was raised that came to perfection. Bosse, a German horticulturist, says that, when seed is to be kept for any length of time, it should be left in its natural covering. Other means of protection are sometimes available to preserve perishable seeds. Acorns will keep, packed in the hard ground, for centuries, and many seeds may be safely kept or transported in honey. Some seeds, like those of the Cucurbitaceæ, the balsam, stock, and wall-flower, improve with age to a certain extent. Many seeds are capable of preserving their vitality for years under ordinary conditions of dry exposure. Experiments by M. Alphonse de Candolle indicated that woody species preserved the power of germinating longer than others, while biennials were at the opposite end of the scale, and perennial herbs lost their vitality sooner than annual ones. Of three hundred and sixty-eight species of seeds fifteen years old, that he sowed, only seventeen germinated, and but few of the species came up. The seed of radish has grown freely at fifteen years; that of Sida Abutilon at twenty-five; those of melon and tobacco at forty; that of the sensitive-plant at sixty. A committee of the British Association reported in 1847, after seventeen years of examination, that the Leguminosæ, considered as a family, appeared to possess more vitality than any other; next came the Malvaccæ, Tiliaceæ, and Croton, of the Euphorbiaceæ, among those kinds whose seeds grow after ten or more years. Apparently well-authenticated instances of seeds that have grown after having been preserved from a remote antiquity are not rare. Plants have been raised from seeds found along with coins of the Emperor Hadrian, in an ancient barrow in England—Medicago and a heliotrope from a Roman tomb, fifteen or sixteen hundred years old, where they had been put in a bag under the head of the corpse for a pillow. The genuineness of some of the specimens of so-called "Egyptian wheat" has sometimes been questioned, but Mr. M. F. Tupper obtained plants from grains which Sir Gardiner Wilkinson took from a previously unopened mummy-case, and gave to Mr. Pettigrew, who gave them to him. Rose-seeds and doura-seeds, the genuineness of whose ancient Egyptian origin is equally well authenticated, have grown, the former with Mrs. Governor Wood, at Quincy, Illinois, the latter with the Rev. Albert Hale, of Springfield, Illinois. Professor John Henry Carroll, of the College of Archæology and Æsthetics of the City of New York, has raised Indian corn from seed taken from a Peruvian mummy supposed to be twelve hundred years old.

A Criticism of Medical Schools.—Dr. Frederic R. Sturgis, in a paper read before the Medical Society of the State of New York, strongly denounces the present systems and standards of medical education. Noticing some unfavorable criticisms that have appeared of the general culture and manners of young physicians, he attributes the origin of the condition which the criticisms expose to the unregulated management of the medical schools. They are nearly all private business enterprises, and have to look to their fees for their support. Hence, while they are always on the alert for whatever may tend to increase their fees, they are easily enough prone to neglect or overlook what may have no direct bearing upon that point, though it may be of the utmost importance in relation to the fitness of the student to become an acceptable practitioner, and a desirable acquisition to the community in which he may settle himself. The charters of medical schools are too easily obtained, and not sufficiently guarded, to make it sure that the school will be a useful agency, or even that it will not do harm. "There is nothing," says Dr. Sturgis, "making the educational candidate for a charter show just cause for its existence, nor anything binding it to give good and proper instruction; hence, as soon as its charter is obtained, it may do as it pleases—teach or not, as it likes; or, if it prefers it, may sell its diplomas." The remedy for this evil is the pecuniary endowment of schools, by means of which they may be able to limit themselves to their proper office of serving as places of instruction and nothing else, and be relieved of the necessity of making their diplomas licenses to practice, "which right ought never to have been given them." Then branches can be taught, such as public hygiene, medical jurisprudence, and the like, which have now to be passed over in silence, or else very superficially taught; and the institution which gives the best instruction will, other things being equal, receive the most students. In a word, the concern of the institution should be, in the language of President Eliot, "to have a very good school of medicine, rather than a very large one."

Provincial Accents among Deaf-Mutes.—A topic has been under discussion in the French Academy of Sciences that involves the question whether provincial accents in speech are or are not the result of local peculiarities in the structure of the vocal organs. M. F. Hément has observed that the deaf and dumb children in a certain institution, who had been taught to articulate sounds, speak with the accent of their country; and he believes that, as they have never heard any one speak, their peculiar accent can only proceed from their having organic conformations like those of their parents. M. Hément is supported by a communication from Mr. W. E. A. Axon, published in "Nature." M. Emil Blanchard, contradicting this view, cited the example of a French-speaking Chinaman with whom he had talked, who had no trouble with his r's; and he suggested that the question could not be considered satisfactorily solved till a number of children of people speaking peculiar idioms had been separated from their parents from birth, and taught to speak a single language. Mr. A. Graham Bell has communicated a paper to the "Academy," stating that, in observing the pronunciation of at least four hundred deaf mutes whom he had taught to speak, he has never remarked any tendency of the kind described by M. Hément. In some cases, it was true, dialectic accents could be detected; but he has always found, on investigation, that such children had been able to speak before they became deaf. M. Hément declares that his opinions are not shaken by Mr. Bell's observations, and even professes to find in them new arguments in support of his own theory.

Insect Enemies cf Forest and Shade Trees.—Dr. A. S. Packard, Jr., of the United States Entomological Commission, Las published a valuable report on insects injurious to forest and shade trees, which is intended, not so much to embody the fruits of any original research, as to give a summary of what is up to this time known of the habits and appearance of such insects as are injurious to the more useful kinds of trees. The amount of knowledge we have on the subject is really scanty enough, and the report is, therefore, largely a simple list of the insects that live upon our more important forest-trees. The matter is eminently worthy of the attention of farmers and gardeners and others, who have the opportunity and are competent to make intelligent investigations relative to it and inform naturalists of what they find out; and such persons are invited to communicate the substance of their observations to the commission. Much has been done in France and Germany, both of which countries possess valuable illustrated works on forest insects. Kaltenbach, in his work on the insect enemies of plants, describes astonishing numbers of insects as found-on some kinds of forest-trees, only a comparative few of which are, however, particularly destructive. Thus, 537 species are injurious to the oak, and 107 are obnoxious to the elm; the poplars afford a livelihood to 264 kinds; the willows yield food to 396 species, the birches harbor 270, the alder 119, the beech 154, the hazel-nut 97, and the hornbeam 88. Among the coniferous trees, the junipers supply 33 species, and 299 species prey upon the pines, larches, spruces, and firs collectively. In France, Perris has observed more than one hundred species either injurious to the maritime pine or living upon it without being especially injurious to it. The number known to attack the different kinds of trees in the United States is sufficiently large to excite great fears for the future prosperity of our diminished forests unless some means are found to check their increase, and the subject of forest entomology is becoming one of really great importance.

Domestication of Wild Ducks.—Mr. Charles Linden has made report to the Buffalo Society of Natural Sciences of the experiments which Mr. George Irwin, of Mayville, on Chautauqua Lake, has been conducting for more than thirty years in the domestication of several species of wild duck. A suitable lot of about an acre in extent, on the edge of the lake, was fitted up with protecting sheds and nesting-places, and stocked from time to time with eggs for hatching, ducklings, and old birds. The pin-tail and American swan freely bred and raised their young in the inclosure, without anymore restraint than was necessary for safe-keeping, but were never fully domesticated, nor even transferred from the breeding-pen to the barn-yard. The dusky duck and mallard, which proved most tractable for domestication or complete metamorphosis into tamed barn-yard fowl, resisted all efforts for this purpose if they were transferred to the pen when one year old, but were readily tamed when they were raised from eggs or captured young. "The majority of them seemed to feel as much at home here as in any nesting-ground of their own choice, and generally returned whenever they were permitted to migrate in autumn." The progeny of the Canada goose as well as of the other species prospered well and became large. Some of the progeny are still living, and betray in many instances a tendency to revert, as to plumage, but the majority have become completely metamorphosed into barn-yard fowl. No hybrids from different species were obtained, except from crosses between the mallard and the dusky duck. The food of all the ducks was what they ate in the wild state—grains, acorns, etc.; and shoots and roots of aquatic plants for the wood-ducks. All the species experimented with migrated southward, if not maimed, each autumn, and invariably returned with a male mate, which remained till the female began to hatch, when it went away, never to return. The crosses obtained with tame birds retained their original plumage to a greater or less degree, but were of increased size. It appears from the experiments that the majority of our wild ducks are not easily prone to change their wild condition for that of perfect domestication, but that they manifest no aversion to breed freely, even when they are placed under artificial restraints.

Siberian Products.—The following facts indicate that Siberia may be destined to occupy a place of considerable importance in the world's trade: Gold, silver, platinum, lead, copper, and iron are found in the Ural. The gold product of that region (nearly all of it being drift-gold) amounted in 1876 to between 140 and 150 centners; and the whole product of Siberia in 1877 was estimated at about 780 centners. Coal-beds exist in the Ural, in the Kirghiz steppes, on the northern borders of the Altai Mountains, on Lake Baikal, and on the Amoor River. Graphite-beds have long been worked in the Shian Mountains, and other graphite beds are waiting exploitation on the lower Tunguska. Agriculture and cattle-raising do not flourish, notwithstanding some favoring circumstances, on account of the deficiency of outlets and labor. The fur-trade is not so important as it formerly was; for the silver-fox, ermine, and sable have become scarce. The fisheries afford an important article of export, but they are carried on in the most primitive manner. The opening of the Arctic Ocean to navigation and the extension of the railroad that now reaches to Ekaterinburg will be of great advantage to the future of Siberia.

Miracles not out of Date.—Dr. Giordano has reported upon a remarkable epidemic of morbid fanaticism which is prevailing in the village of Alia, in Italy. The place is almost inaccessible, having but little intercourse with the world, and is marked by a barbarous style of living, and by the prevalence of intermarriage, with its usual concomitants of weak-mindedness, morbidness, and idiocy; consequently, superstition flourishes. After a long drought in February, March, and April last, a religious procession was organized to obtain rain. The statue of Saint Francis was carried round, and the declaration of a fanatic that he saw water flowing on the face of the saint was readily taken up by the credulous crowd. The miracle was attributed to the intercession of a girl named Rosalia Giallonbarda, who, having formerly suffered from epilepsy, believed she had been cured by the saint, and was the subject of an excessive mysticism, with hallucinations. Her frenzy was caught by her relatives and neighbors, and spread abroad till the crowds of fanatics coming to visit her and the saint became so formidable that she was arrested. This "sacrilege" only stimulated the popular excitement.

Silk-spinning Spiders.—The spiders, large Epeiridiæ, which produce silk, inhabit the hottest countries. They are represented in our latitudes by a few species of inferior size, the most common of which, the Epeira diadema, is very numerous in gardens in the fall, and may be remarked by the regularly shaped webs which it weaves among the bushes. These delicate gauzes, however, give only an imperfect idea of the webs that are woven by the larger species of tropical regions. In India, the Sunda Islands, Madagascar, Réunion, and Mauritius, the Epeiræ construct webs of extraordinary dimensions, and the traveler has frequent cause to admire the threads which he finds strung across the water-courses, and fastened to the trees on the opposite sides. The threads of these spiders are of different kinds, and proceed from different glands. The silk which is wrapped around the cocoons is not the same that is spun in the webs, and may be of an entirely different color. The silks of various Epeiræ were brought to Europe by travelers in the seventeenth century, and excited admiration by their fineness and brilliancy. Experiments were tried in making cloth and gloves from them, but they were found to have no powers of endurance. Louis XIV, wishing to encourage a new art, had a coat made of the silk, but was glad to take it off the first day, for it suffered a rent every time he moved. These efforts appear to have been made with the silk of the webs. That unrolled from the cocoons proved to be stronger. M. Bon, in 1709, carded from the cocoons a silk which he described as much finer and stronger than ordinary silk, and which, he claimed, was fitted to make any kind of fabrics. In Spain, Raymondo María de Tremezer, between 1777 and 1791, made several articles as bright and fine as silk from the threads of the Epeira diadema. Mr. Rolt, an English merchant, was able to exhibit to the Society of Arts a specimen thread twenty thousand feet long, that had been spun by twenty-two spiders in less than two hours, and which was five times as fine as the thread of the silk-worm! Alcide d'Orbigny asserted that he had garments, able to sustain considerable wear, made in South America from spiders' silk.

Food and Civilization.—M. Beketoff, a Russian hygienist, has expressed some novel views in a paper on "The Alimentation of the Human Race in the Present and the Future." Physiologists are accustomed to consider a mixed diet, of which meat shall constitute about one third, to be the best for mankind in general, and to be almost essential to the best development. M. Beketoff does not consider this view to be well founded, or sustained by the facts as they appear on examination of the diet of the best races. A large majority of mankind do not use meat, nor a mixture of meat and vegetables, but vegetables alone, as food. The people of Europe consume more meat than those of any other part of the Old World, but most of it is used in the cities, while the country people enjoy only a small fraction of the quantity which the physiologists say they need, and it has come to that point that, in the most civilized part of the world, meat is only not wholly left out of the list of common foods. In the most populous and most civilized parts of Asia, as in China and India, cattle-raising is quite insignificant, and in Japan can hardly be said to exist at all. The Africans raise cattle, but live chiefly on vegetables. Only in North and South America and Australia is meat consumed on a really large scale. Not only the relative, but the absolute number of cattle also, shows a tendency to diminish as the population increases and the ground is more devoted to tillage; so that the prospect is apparent that, with the continuous development of agriculture, industries, civilization, and population, cattle-raising will pass into real insignificance, and the mass of men will be unable to obtain animal food. Sources of vegetable food must be found, to supply its place, among the plants richest in albuminous substances. The legumes are the most prominent of these plants. To determine the power of beans to sustain all the functions of life, Dr. Virochiloff performed a series of experiments upon himself, by eating regularly equal quantities of bread and sugar, and adding to them for a certain time meats, for another period peas. The result was, in his own words, that "both the mixtures quite fulfilled the purpose of nutrition, as was proved by the same weight of body being kept up and the forces being maintained in the same state by either food." The meat-mixture was, however, assimilated more readily than that of which the peas formed a part. It is affirmed that men occupied in intellectual work especially need a mixed food; but of this we are not certain, not knowing on what those whose intellectual achievements have been greatest have really lived; and many of them have been very irregular eaters. Taking the history of the human race as a whole, we may observe that races living almost exclusively on meat have been and are the most savage ones. The prehistoric "finds" show that the beginnings of civilization and of the cultivation of plants kept pace with each other. This does not prove that a meat diet is opposed to civilization, but that the necessities of people who are dependent on meat for food hinder advance in civilization. They have to be hunting, and wandering about from place to place. It is when they have learned to till fields and tame animals, and have become fixed in homes, that they find time to cultivate arts. The Arctic savages are fish hunters, the barbarians of the Asiatic steppes depend on their herds, the meat eating Turks and Mongols were more barbarous than the vegetable-eating Hindoos they conquered, and were the authors of the woes of that suffering people, M. Beketoff's conclusion is that a vegetable diet contributes more than any other to the intellectual development of a people, while a wholly animal diet determines a kind of life incompatible with progress. A mixed diet has not been the promoter of civilization, for the most highly gifted authors have often drawn their physical forces from a wholly vegetable diet. Finally, "the great thing is evidently not the kind of food, but the kind of life that the food determines."

Synthesis of Indigo.—One of the most important of the recent discoveries in chemistry is that which Baeyer has made of a practical process for the artificial production of indigo. The successful experiments of this chemist had been foreshadowed by the production of alizarene, the coloring principle of the madder-root, from the anthracene of coal-tar; by the discoveries by Fritsche of the relations of indigo with the benzene ring and the amido-group; by Erdmann and Laurent's discovery that indigo on oxidation yields a crystalline body possessing no coloring power, to which they gave the name of isatin; and by Baeyer and Emmerling's accomplishment of the reverse process of reducing isatin to indigo. Three processes have been employed for the synthesis of indigo, of which, however, only one, by Baeyer, is of practical importance. The three processes have in common that they all proceed from some compound containing the benzene nucleus; that they all start from compounds containing a nitrogen atom; and that they all Commence with an ortho-compound. They differ from each other in that Baeyer's process requires the abstraction of an atom of carbon, while of the others one requires the addition of an atom of carbon, and the second starts with the right number of atoms of carbon. Baeyer's successful process, which may be called the manufacturing process, starts from cinnamic acid, a substance which is contained in gum-benzoin, balsam of Peru, and a few other aromatic bodies, but which can be obtained more cheaply by manufacturing it artificially. Bertagnini has obtained it from oil of bitter almonds; and other processes for the same purpose have been carried out. One of the processes most likely to be adopted is that of Dr. Caro, who converts toluene, by adding chlorine, into benzylene dichloride, and treating the latter substance with sodium acetate, forms cinnamic acid and sodium chloride. The next steps in the process are the formation from cinnamic acid of ortho-nitro-cinnamic acid; the conversion of this into its di-bromide; the separation from this of the two molecules of hydrobromic acid, which gives rise to ortho-nitro-phenyl-propriolic acid; and, lastly, the conversion of the latter product into indigo by heating its alkaline solution with grape-sugar, xanthate of soda, or some other reducing agent. The actual yield of indigo by the last reaction has not been made equal to what is demanded by theory, it being only 48 per cent, while the theoretical yield would be 68 per cent. The artificial production of indigo by this process may be considered as within reasonable distance of commercial success, for the orthonitro-phenyl-propriolic acid, the colorless substance which, on treatment with a reducing agent, yields indigo-blue, is already in the hands of the Manchester calico printers, and may be obtained at the price of six shillings per pound of a paste containing 25 per cent of the dry acid. Indigo can not, however, be made profitably from this product till the theoretical yield can be obtained from it, and until the price of the dry propriolic acid can be reduced to 20s. per kilo, or 8s. ($2.00) a pound. The process may, however, be found applicable with advantage even at present rates, for uses for which natural indigo is unfitted. Of the other processes for manufacturing indigo, the first starts from ortho-nitro-benzoic acid, which yields isatin after successive treatment with phosphorus pentachloride, silver cyanide, caustic potash, and nascent hydrogen. The other, also by Baeyer, starts from ortho-nitro-phenyl-acetic acid, which, having been obtained synthetically from toluol, is converted into the amidoacid, then by the loss of water into a body called oxindol, from which isatin, and therefore indigo, can be obtained.

Tobaccoism.—M. Thorens has published some observations on angina pectoris caused by tobaccoism. His attention was called to the subject by the case of a patient who had most of the symptoms of angina pectoris, but in whom no cause for the affection could be found except excessive smoking. The patient smoked cigarettes, and swallowed the smoke, thus making the whole quantity of smoke pass through the lungs. Evidently the opportunities given for the absorption of smoke and nicotine in this case were colossal in comparison with those which would exist in a person smoking ten times as much, but in an open place and without swallowing the smoke. Another circumstance aggravating the affection was, that the patient smoked his cigarettes directly, without the intervention of a holder, so that the smoke reached his mouth hot, without any chance having been given for the condensation of any of the volatile products. His mouth was, moreover, in constant contact with the tobacco-leaves, so that the liability of absorption by the buccal membrane was greatly increased. Similar affections arising from similar causes had been noticed by Beau and M. Gélineau, a naval surgeon, both of whom observed that the trouble was mitigated when the use of tobacco was moderated. The case suggests a number of precautions to be observed by persons who will smoke but desire to do themselves as little harm as possible, among which are never to swallow or inhale the smoke; to avoid smoking in an inclosed place, or at least to have the room as large and as well ventilated as possible; and to put as considerable a distance as is practicable between the light and the mouth, always using for this purpose long-stemmed pipes or cigar-holders. The driest tobacco and that which is weakest in nicotine, should be preferred. M. Thorens exonerates tobacco from the charge of producing cancer, although it is of course liable to irritate a wound already made, or a surface that has already been injured by heat.

The Horse in America.—It has been generally believed that the horse was introduced into America by the Spaniards. Professor Marsh, on the other hand, has found abundant remains of probable ancestors of the horse in our Western geological formations; so that, if there were no horses before the Spaniards came, there must have occurred a failure of the race. Mr. E. L. Berthoud, of Golden, Colorado, believes that he has evidence that the Spaniards found horses in South America when they first visited it. Among the maps which he has recently received from Paris, in a collection of the fifteenth and sixteenth centuries, is one which Sebastian Cabot drew for the Emperor Charles V, representing his explorations of the La Plata and Paraná Rivers, and containing symbols of the animals and plants that he found. Among these symbols was that of the horse represented near the plains of the Gran Chaco, where the immense herds of that animal range to-day. He claims that this affords a fair presumption of the native origin of the race, for neither the Spaniards nor the Portuguese had then been long enough in the country (in 1527) for their horses to have escaped from Peru to the head of the Paraguay and Paraná Rivers and to have increased in numbers sufficiently to attract attention.

The Protective Organs of Plants.—Dr. A. Tschirch has recently published some interesting observations on the relations of the anatomical structure of plants to climate and location. In the first place, the adjustment of the breathing-pores appears to be adaptable to a variety of external conditions in different plants of the same family. In plants that grow in a moist atmosphere, the pores are exposed with but slight protection; while the means of protection appear to increase gradually as the habitat becomes drier, and reach the highest point in desert plants. The closed cells that lie partly outside of the epidermis enjoy the least protection, as in certain ferns, while a higher degree of protection is given when the cells are sunk beneath the epidermis and framed in a kind of funnel; and the highest degree when the stomata are arranged in rings or ovals on the under-side of a rolled leaf. Another means of protection is afforded by the structure of the epidermis, which is fortified by a strong cuticular structure, hardly permeable to vapor in many Australian plants, and is sometimes re-enforced by deposits of oxalate of lime. Such structures are peculiar to plants which have to sustain great drought. The epidermis of many plants, as the Eucalyptus globulus, is also covered with a coating of wax, which serves not only to protect it, but also to give a deeper setting to the pores. The protective effect of hairs operates in several ways: they cover the pores; they form a kind of space over the pores in which air and vapor may collect; and they constitute a kind of screen over the whole body of epidermis-cells against insolation and desiccation. Thus, plants growing on high, dry mountains, or in the steppes, are generally thickly haired. Hairs also serve to make the plant measurably defiant of sudden changes of temperature, and form an important part of the vegetable economy of regions like Soodan and continental Australia, which are subject to such changes. Even in temperate climates, varieties of the same species growing in open and exposed places are more hairy than those growing in protected woods. In the eucalyptuses the intercellular spaces and air-passages of plants growing in dry situations are much contracted, while in those growing in valleys and along rivers they are expanded. Willkomm has called attention to the fact that a sap strong in saline solutions is much less subject to evaporation than a thinner sap; and thus the halophytes keep fresh in stony places and the driest climates, while the Chenopodiaceæ (goose-foots), with much salt in their juices, flourish in dry places, and are met abundantly in the Asiatic steppes and the interior of Australia; and these look green and vigorous in the driest time of the year, when everything else is parched and brown. The form and position of the leaf also often show an adaptation to help the plant resist drought. Plants having to grow in a dry climate generally exchange the usual broad leaves for a narrow, close one, have it reduced to a cylindrical form, or, as in the brooms, make a green limb serve them as the assimilating organ. Broad leaves are seldom found in very dry regions. Many species peculiar to hot and dry situations have a faculty of arranging their leaves vertically, so that only the edge is exposed. The Lactuca scariola, the only European plant having this peculiarity, grows on roadsides and dry hills, while all the other species of lettuce, growing in shady and moist places, and in gardens, have the leaves arranged in the ordinary way, except that Lactuca sativa puts out vertical leaves when it is growing in a thin soil. The ethereal oils and thorns of plants may also possibly serve some protective purpose, but this is a subject for further investigation.

Terra del Fuegians in Paris.—Eleven natives of Terra del Fuego, four men, four women, and three children, were taken to Europe by 31. Waalen, who has resided for several years at Punta Arenas, Patagonia, and have been entertained at the Jardin d'Acclimatation in Paris. M. Waalen was fishing for seals in the waters of their inhospitable island when he came in contact with these savages, and succeeded, by giving them plenty to eat and treating them with tact, in getting them to stay on his vessel, whence they were transferred to a Hamburg steamer on its way to Europe, M. Waalen depositing security with the governor of Punta Arenas for their safe return after making their European tour. What mark their visit will make upon them, and how long it will endure, is a question which the experiment of Captain Fitzroy may help to answer. He took back three Fuegians, two men and a woman, after they had been three years in Europe, and had seemed to become nearly civilized, and set them among their tribe, in a good house, with a tract of tillable land, tools, and a missionary to take care of them. Going back to see them a few months afterward, he found all that pertained to civilization destroyed, that they had returned to complete savagery, and that the missionary was anxious to get away from them. The Fuegians in Paris are described as accustomed to squat for hours, without moving, around a fire on the lawn, perfectly indifferent to everything, and listlessly looking at the crowd who peer at them through the bars of the fence as if they were some extraordinary animals, and as occasionally exchanging with each other the guttural duckings which serve them for a language. Only one thing will excite liveliness in them—the desire for food.

Forms of Aurora Borealis.—Lieutenant Weyprecht, in his recent work on the observation of the aurora borealis, distinguishes between seven forms in which the light appears in the polar regions. The first form is that of almost regular arches rising or sinking from the magnetic south or north to or away from the zenith, and generally extending to both sides of the horizon. Second, are streamers of irregular form and varied appearance, appearing like bands much longer than broad, moving in the atmosphere, and nearly always bent in folds and twists; they consist either of masses of light unequally distributed along the length of the band, or of single beams of the breadth of the band closely arranged together in a direction toward the magnetic zenith, and having their intervals filled with light-masses. This form is cut away on every side, or at most touches the horizon on only one side. Of the third form are threads, extremely fine beams of light of various lengths, some of them reaching from near the magnetic zenith to near the horizon, and grouped in such a manner as to resemble a fan covering a part of the firmament. The beams are not united, but are separated by dark spaces of greater or less width. Generally, they are prolongations of a streamer, which in such case answers to the continuous lower border of the fan. Fourth, is the corona, in which the beams or light-masses are joined in a common center near the magnetic zenith, and a constant movement is maintained toward or around the same. Fifth, haze dim, unformed accumulations of light-masses illy defined, at some point in the firmament. Sixth, the dark segment, a darker appearance, forming a segment of a circle, in the magnetic north or south, bounded by a fixed and low seated bow of light. Seventh, the polar shine, an illumination of the polar sky, the form in which the light generally appears in middle latitudes, but which is not observed in its home. Its characteristic feature is that the rays diverge from the horizon up, while the divergence in all the other forms, if their rays can be distinguished, is in the reverse direction. The movements of the mass consist either of a rising and sinking of the rays and arches with reference to the horizon, a lengthening, and shortening, and sidewise motion of the threads, or a general change of place. The mass has also motions within itself, which may consist of undulations or flashes of the light. The undulations are waves, streamers, or partial arches, which pass along generally from the magnetic east or west, toward the opposite end of the phenomenon, and then appear to spring out from it. The flashes are the shooting of short, broad beams, with the velocity of lightning, from the streamers toward or from the zenith. They are the forerunners or accompaniments of intensive coronas, and originate in particular when a stream of rays merges into the corona.

Wyville Thomson.—The death of Sir Charles Wyville Thomson, in the fifty-fourth year of his age, is announced. He was born in Linlithgow, Scotland; began his medical training at Edinburgh University in 1845; held a Lectureship on Botany at King's College, Aberdeen, in 1850; and has occupied professorial chairs in science at King's College, Cork, Belfast, and Edinburgh, where he succeeded Professor Allman as Professor of Natural History in 1870. He has contributed many papers of merit to scientific societies and periodicals, beginning with ono on the application of photography to the compound microscope, which was read before the British Association in 1850. His most distinguished service, and one by which he won an enduring fame, was as Director of the Civilian Scientific Staff of the Challenger Expedition, where he gave unremitting personal attention to the dredging operations, and the examination of specimens. He had been for some time in feeble health, and his death followed his becoming severely chilled on a visit to Edinburgh. "Sir Wyville was an excellent lecturer, a most genial companion, and an excellent host," and was fond of amusements of all kinds.