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

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POPULAR MISCELLANY.

The Sanitary Problems of New York City.—Professor W. P. Trowbridge, discussing "The Sanitary Problems of New York City," in the "School of Mines Quarterly," considers chiefly the ventilation of houses and the condition of the streets. The topography of the city, presenting long rows of closely built blocks of dwellings and stores, and of the narrow streets that separate them, is a very obvious sign of the close crowding of a large population into a small space which actually exists. This crowding is of itself a great sanitary evil. If, says Professor Trowbridge, we may take a lesson from nature in the distribution of other classes of the animal kingdom, we find that the herding together in confined places of any one class of animals is detrimental to the health and well-being of the individuals. Diseases peculiar to the class of animals are apt to arise, and a general physical deterioration takes place. "As an animal, man is not exempt from this law of nature, unless, through his own superior intelligence, he secures to himself immunity from the evils which over-crowding entails." A momentous question in our city life is whether, in the construction of our houses, and stores, and hotels, and public halls, the quantity of air which each person requires for his health is provided for by processes or appliances of ventilation. The quantity of air required for a healthy life is generally estimated by the number of cubic feet needed for respiration alone. This is a mistake. Each person needs vastly more—enough to secure a thorough aëration of his clothing and to destroy by oxidation all the hurtful emanations of the body. In houses, moreover, the needs of large quantities of pure air for the aeration of clothing, basements, kitchens, closets, and the closets in which clothing is kept, are probably as great as for respiration. Yet, "how few of the houses in the long blocks which constitute the city of New York have been constructed with the slightest reference to the constant introduction and removal of air!" All of our houses are provided with four or five chimney-flues which might be made available for ventilation to a certain extent, but in the use of which it is so little thought of that the rooms, that might be connected with them, are hermetically sealed from them. The kitchen or basement, where there is necessarily an accumulation of deleterious gases, or impoverished air, is perhaps the worst ventilated room in the house. The people still need to be convinced that ventilation is necessary, and that force must be used to move the air. The object can be secured by means of vertical ventilating flues of sufficient suction, but the application of heat either by a gas-jet or other artificial means is requisite to keep them in operation. The matter of the dirt in the streets has an important sanitary aspect. From this point of view, Professor Trowbridge thinks it is worthy of consideration whether an entirely new treatment is not advisable. Heretofore, attention has been confined to the removal of the dirt as it accumulated; Professor Trowbridge would have means adopted to prevent its accumulating. "The dirt that covers the streets as they are now paved does not come entirely from above or from any external source, but is forced upward from beneath the pavements by the impact of the trucks, carts, carriages, and horses' hoofs, in the ordinary traffic of the city. It is doubtful whether it is possible to keep the streets reasonably clean, even with an expenditure of double the present outlay for that purpose. The soil on which the pavements are laid is not a soil which effects its own drainage, and each successive shower or storm saturates the surface beneath the paving, the water carrying down the leachings of the streets; and this soil, permeated with decomposing substances and saturated with polluted water, is forced to the surface. No better medium for retaining and giving off malarial gases could probably be manufactured. When dried, this expelled mud becomes dust, and is carried about by the winds into every household. The real cure of this great evil appears to me to be an impervious pavement—an asphaltic pavement." No dirt could rise through this, and, if every street in the city were paved with it, what dirt falling upon it was not carried off naturally by showers into the sewers could be thoroughly removed by mechanical sweepers without dust or noise. The resulting purity of the surface of the streets would have an excellent aesthetic effect upon the population, particularly on those who live in the dirty streets, and would prompt them to purify their own homes, make them pleasant and adorn them—works from which they are now discouraged by the public filth that surrounds them, and which they can not help. Other sanitary improvement would follow the general adoption of these pavements, in the relief from nervous disorders which would be gained by the cessation of the noise of the stone pavements and the worry from their dust and joltings. "The time has come when the sanitarian must extend his field even beyond mere physical causes of disease, and look to the palliation of the effects of incessant struggles and conflicts which a business man of the present day must undergo. . . . Quieting influences are worth almost any price, and these should be sought and provided along with those which relate to physical health."

Origin of Domestic Dogs.—Professor Huxley, in the second of two lectures on dogs which he recently delivered at the Royal Institution, examined the peculiarities of the animals of the dog kind, and pointed out that the only respect in which the varieties presented any very great or remarkable difference, apart from the color of the skin or fur and other minor details, was in the structure of the skull and in the teeth. The form of dog which departed most widely from the rest in its dentition was the octocyon, a small, fox-like creature belonging to South Africa, which had forty-eight teeth, while other dogs had forty-two. The dog-like animals might be divided into two classes according to the peculiarities of the skull—those like the wolf, or the thooids, having a great cavity over the brow which causes the front to be prominent; and those like the fox, or the alopecoids, which are without this cavity. This enabled them to fix the position of the domestic dogs still more definitely; it would occupy a place in the series corresponding with that in winch they had put the jackals and wolves. With regard to the stag-hound, the shepherd's dog, and many of the cur-dogs, no one would have the slightest hesitation in placing them just between the wolf and the jackal. Some domestic dogs had as large a development of skull as the wolf, but the appearance of sagacity it gave them could not be depended upon, for it was often due to the existence of the cavity. Speculating upon the probable origin of the domestic dog, Professor Huxley called attention to the fact that, in Northwest America, the Indian dog was not really distinguishable from the prairie-wolf. The domestication of these animals was easily explicable when it was remembered that, although fierce enough when stirred up, they were endowed with singular curiosity, which attracted them particularly toward man and his doings, and that, when caught young and kindly treated, they soon became as attached and devoted to their masters as ordinary dogs. A domesticated stock might thus have readily been produced. If this one domestic dog had originated in the taming by man of an indigenous wild animal, then the general problem of the original taming of domestic dogs would take this form: "Can we find wild stock so similar to the existing dog that there is no improbability in concluding them to be the same animals?" He thought we could. We might trace dog-like animals farther and farther west until, in northern Africa, we had a whole series of kinds of such animals usually known as jackals, presenting every conceivable gradation between the characteristic of the dog and the characteristic of the jackal. He believed these wild stocks were the source whence, in each region of the world, the savages who originally began to tame dogs had derived their stock. This was confirmed by the latest archaeological evidence. The monuments of ancient Egypt had preserved a great variety of dogs, but it was an interesting fact that the oldest monuments contained the smallest number of varieties, and in the third and fourth dynasties there were only two well-marked forms of dogs—one a small, cur-like animal, resembling the one that now haunted the streets of Cairo, and the other of a form more like that of the greyhound. The cur was, no doubt, a tame species of the wild jackal, which was still to be found in the same country; and, with respect to the greyhound, there was in Abyssinia a very long-headed dog, which was very much of the same form as the greyhound, and which it could hardly be questioned was the source from which it sprang. Assuming that the origin of the dogs could be traced to these sources, the more modified forms of the domestic animal were simply the result of the selected breeding which had given rise to similar modifications in dogs as it had done in the case of pigeons. Referring to the origin of dogs in general, Professor Huxley noticed the discovery of a fox-like animal of the Pleiocene period, which was found near the Lake of Constance. An animal, the cynodictus, lived in the upper Eocene period whose dentition was substantially that of the dog, and which appeared to bridge over the wide interval that separated the bears and animals of that order from dog-like forms. Beyond that period there was no distinct trace of doglike animals. By the application of ordinary common-sense reasoning, which was verified every day by experience, they were driven to the conclusion that they could only attribute the origin of these animals to causes which operated in the existing course of nature. This left them to the simple alternative of the doctrine of evolution. He believed that small differences of form—slight modifications of one main plan—were amply sufficient to give rise to the existing dog-like animals, and that these modifications had actually taken place, starting from the cynodictus.

Efficiency of Lightning-Conductors.—Direct evidence as to the efficiency of lightning conductor is afforded in a government report from Schleswig-Holstein, which is referred to in a recent work on the subject by Mr. Richard Anderson. Thunderstorms are said to be more numerous in Schleswig Holstein than in any other part of central or northern Europe, and the danger from lightning is correspondingly increased. The attention of the government insurance-office was called to the fact that, in four out of 552 cases of claims on account of damage from lightning arising in eight years, conductors of approved design had been in use, and an expert, Dr. Holtz, of Greifswald, was appointed to inquire into the causes of failure. He found that, in every case where a building provided with a conductor had been struck by lightning, the conductor was not in an efficient state. Sometimes the point of the rod was needlessly ornamented with gilding, while the underground connection with the earth, the very element of safety, was neglected. In the absence of a proper ground connection, the lightning-rod, instead of being a protection, may prove the means of attracting the discharge into the building. A measure for the periodical testing of conductors is suggested, for the detection of defective constructions, interruptions of conductivity by rusting or displacement, or of other faults that may arise from time to time.

Atmospheric Currents and Carbonic Acid.—M. Marié Davy, of the Observatory of Montsouris, France, has made a report of observations which he has taken for four years on the proportion of carbonic acid in the air as it is related to the grand atmospheric movements. The quantity of this gas is found to vary from twenty-two to thirty-six parts in one hundred thousand parts of air. During the earlier observations, extending to December, 1877, the proportion of carbonic acid was below the mean, and sometimes fell very low. In a second period, from December, 1877, to September, 1879, the proportion was considerably above the mean. A third period began in October, 1879, which was characterized like the first period by a relative weakness of proportion. The weakness became remarkable in December. The second period, in which the carbonic acid was superabundant, was characterized by moist weather with a predominance of the equatorial current over France, and embraced two years of short crops. The first period was characterized by an inferior extension of the equatorial current, by less wet weather and better crops. During all of the time of the observations, the proportion of carbonic acid showed no variation to correspond with the changes of the wind or the indications of the barometer, thermometer, and hygrometer. The fall of rain had no definite effect on the proportion. It thus appears that the proportion depends on the general predominance of the equatorial current, and not on the temporary changes of weather.

An Electrical Experiment of the Eighteenth Century.—The apparatus here represented is composed of a globe of sulphur which a young abbe causes to turn by means of a crank and wheel, while the woman excites electrical action by means of the friction of her hand on the ball. A young man suspended horizontally by cords of silk becomes electrically excited, and causes the spark to fly from the end of his finger by

AN OLD ELECTRICAL EXPERIMENT.

putting it near a stick which another experimenter extends toward him. Experiments of this kind were much in fashion about the middle of the last century. They assumed many variations, but the one here represented was repeated frequently. The contrast between this simple apparatus and the hundreds of machines from the most delicate to the most powerful, applicable to a wonderful variety of purposes possessed by the electricians of the present day, helps us to realize the amazing rapidity with which improvements are made, and justifies the liveliest hopes for the advancement of electric art in the future.

Lessons from the Tongue of the Bee.—Professor A. J. Cook publishes, in the "American Bee Journal," some extremely interesting conclusions, which he has derived from the study of the tongue of the honey-bee. The accounts of the entomologists who have written upon the construction of this organ are conflicting and generally inaccurate. They do not agree as to its shape; some say that it is solid, others that it is tubular; some that the insects lap the liquids in which they feed, others that they take it by suction. By combining the studies that have been made by Mr. V. T. Chambers and Mr. J. D. Hyatt on the anatomy of the tongue of the bee with his own investigations, Professor Cook has been convinced that those who believe that the liquid is lapped up, that it is sucked through the tongue as a tube, and that it is drawn through a tube which is formed by the approximation of the ligula (or tongue), the palpi, and the maxillæ, are all right. The physiology of the tongue and the related organs adapts them to use in either of these methods; the bee has been detected in gathering nectar by all of them; and the presence of the fluid in passage has been demonstrated in the several organs the use of which is required by the different theories. The honey appears to be most abundantly secured by means of the tube formed by the closing up of the ligula, the palpi, and the maxilla. The ligula, or tongue, extends several hundredths of an inch farther than the labial palpi, and is itself provided with a rod and slit which may be made a tube, and a funnel for gathering nectar. This instrument appears to be the only one which is available for use in gathering honey from small tubular flowers; and the examination of its construction explains why bees are so much longer in gathering from some flowers than from others, as those in which the combined tube is available. It is also probable that bees lap honey. The measurements of the tongues of bees show a uniformity in the length of those of bees from the same colony or apiary, but considerable difference in those of different breeds. In the same colony, tongue after tongue would show a variation of less than 0·25 of an inch from the base of the mentum to the tip of the ligula. The average length of the American black bee's tongue is about ·24 of an inch; that of the Italian bee is about ·02 of an inch longer. The longest tongues were found in some Cyprian bees. The difference in the length of the tongue is accompanied by a corresponding difference in the capacity of the bees for gathering honey. Honey in a vessel covered with fine gauze was placed before some Italian bees till they ceased to eat because they could no longer reach it. It was then placed before the black bees, but they could not reach it. A similar dish was given to the black bees first, and, after they ceased eating, the Italians continued to sip. Many trials gave similar results. This shows how the Italians can gather honey from flowers which fail to attract the black bees because the nectar is beyond their reach. It thus seems probable that the law of natural selection, which raised the Italian bees to their position of superiority, also gave them their longer tongues. Shut up in a narrow basin among the mountains, with only a limited range for food, competition must have been excessive among them, and the variations which gave any of them advantages over the others would come into the fullest play. Similar conditions may have determined the character of the Cyprian bees and other superior varieties of Europe.

The Violin: its Construction and Perfection.—In a lecture, which he recently delivered at the Royal Institution in London, on the construction, the history, and the sound of the violin, Mr. Haweis called attention to the variety in shape and style of instruments of the viol tribe, ancient and modern, as showing the inexhaustible fascination they possessed over the human mind. The wood was selected by the best makers of the old violins with extreme care. At Brescia, they used pear, lemon, and ash; at Cremona, maple, sycamore, "and, of course, pine. . . . The wood came into the markets of Mantua, Brescia, Cremona, Venice, Milan, from the Swiss southern Tyrol, unlimited in supply, often mighty timbers of great age—plentiful then, scarcer now. The makers had their pick; they tested it for intensity and quality. Cut strips of wood and strike them: you will see how they will vary in musical sound. When a good acoustic beam was found, the maker kept it for his best work. In Joseph Guarnerius and Stradivarius the same pine tree crops up at intervals of years. A good maker will patch and join and inlay, to retain every particle of tried timber. Old wood is oddly vocal. As I sat in my room, surrounded by these instruments, I could not cough or move without ghostly voices answering me from the sixteenth, seventeenth, and eighteenth centuries; and even the old-seasoned backs and bellies of unstrung violins are full of echoes." Taking a violin and tearing it open, the lecturer continued: "The violin is made of fifty-eight or seventy pieces. It is a miracle of construction. It is as light as a feather and as strong as a horse. Wood about as thick as a half-crown, by exquisite adjustment, resists for centuries a pressure of several hundred-weight. The belly of soft deal, the back of hard sycamore, are united by six ribs of sycamore, supported by twelve blocks with linings. The sound-bar, running obliquely under the left foot of the bridge, is the nervous system of the violin; the sound-post, supporting the bridge, is the soul; through it pass all the heartthrobs or vibrations generated between the back and the belly; on its position depends mellowness, tightness, or intensity of sound. The prodigious strain of the strings is resisted first by the arch of the belly, then by the ribs, strengthened with the upright blocks, the pressure among which is evenly distributed by the linings which unite them, and, lastly, by the supporting sound-bar and sound-post and back." The secret of the ancient varnish, on which some of the qualities of the instrument probably depended, is still only partly revealed. Mr. Haweis believes, with Charles Reade, that it was an heterogeneous varnish, first of oil with gum in solution, then of color evaporated in spirit. Dod, as late as 1830, had the recipe for something very like the Cremona varnish; and, lately, Mr. Perkins has analyzed the varnish of Joseph Guarnerius and found amber in it, and has himself produced varnish of an extraordinary quality. The supreme interest of the violin lies in its simplicity, beauty, strength, subtilty, and indestructibility, and, above all, in its perfection as a musical instrument. It combines accent with modification of sustained tone. The organ has sustained tone without accent, the piano accent without sustained tone, the violin accent and sustained tone modified at will. Within its limits it is scientifically perfect; it has all the sensibility, and more than the compass, execution, and variety, of the human voice. It is not an invention, it is a growth; it has come together, it is the "survival of the fittest." Its rough elements were selected from a variety of instruments which preceded it. Before the end of the fourteenth century viols were made in great profusion of every style and shape, but the rise of the true violin tribe begins with the rise of modern music. When the true octave and the perfect cadena had been discovered, and the human voice was found to fall naturally into soprano, contralto, tenor, and bass, viol instruments, adapted to these four divisions, were gradually separated from the confusion of instruments and brought to a perfection of adaptability.

A New Anæsthetic.—Bromide of ethyl is recommended by Dr. R. J. Levis, of the Pennsylvania and Jefferson College Hospitals, Philadelphia, as an anæsthetic preferable, in most respects, to ether and chloroform. It acts rapidly, and the patient recovers quickly from its effects. As far as observed by Dr. Levis, after several months of experience in using it, it does not influence the circulation except sometimes to produce a slight increase in the rapidity of the heart's action, and in arterial pressure. Respiration is but little affected by it beyond its producing the ordinary characteristics of all anæsthetic sleep; in this respect, its action seems more to resemble that of ether than that of chloroform. Nausea and vomiting occur less frequently with it than with ether or chloroform. It vaporizes readily, and seems to be entirely eliminated through the lungs, having, in this respect, a decided advantage over chloroform, which is not entirely removed from the system. Its vapor produces no irritation in the respiratory passages. General excitement and the tendency to struggle occur far less frequently when it is used than in the early stages of the anaesthesia of ether, and, apparently, even than in that of chloroform. Complete anaesthesia is accomplished, it is estimated, in about one third less time than is the case with chloroform, and recovery from the effect is even comparatively more rapid, the time required for recovery generally not exceeding two minutes after the inhalation has ceased. The recovery is so complete that the patient is often able to stand and to walk immediately after awakening. Insensibility is usually produced in from two to three minutes. The longest period that has been required in Dr. Levis's practice was four minutes, the shortest one minute. The completion of the effect is clearly shown by the dilatation of the pupils of the eyes, which resume their normal condition when the sentient state returns. The vapor of this substance is not inflammable, so that it is free from the danger which attends the use of ether at night when lights are around. The ordinary essentials of the proper and safe production of anæsthesia must not, however, be dispensed with in the use of the new agent, for its safety is only comparative, and is not yet proved to be absolute. Dr. Levis, who acknowledges his indebtedness to Dr. Lawrence Turnbull, of Philadelphia, for the suggestion of this agent, now uses the bromide of ethyl, to the exclusion of other anæsthetics.

Slave-making Ants.—It may be edifying to such persons as take pride in physical prowess to know that on the battle-field ants distinguish themselves quite as signally as do human beings. Mrs. Mary Treat, in the "American Naturalist," thus describes a contest which she witnessed between slave making ants and black ants: The former were the aggressors, and victorious. The two colonies were one hundred and twenty feet apart. An idea of the numbers constituting the ranks of the slave-makers may be gathered from the fact that on the warpath, one hundred and twenty feet in length and a foot wide, they "were not thinly scattered, but a vast moving phalanx." The blacks, a grand army on their own territory, would not flee. The battle-field was about twenty-five feet in circumference. A roar announcing the beginning of hostilities lasted for five minutes, "whereas the battle lasted four or five hours before the reds gained possession of the vast nurseries of the blacks," and it took two days to carry the pupae and prisoners to their own dominions.

Epidemics.—Sir Joseph Fayrer, in his address delivered before the Epidemiological Society of London, on the subject of epidemics, gives some interesting facts regarding typhoid fever and cholera in India. It is well known that typhoid fever is a prolific cause of mortality among European soldiers there, and questions of great practical importance arise in regard to the age, time, and seasons for sending men to the army in India. It appears from the statistics that this disease tells most severely upon the young men during their first year of service; and Dr. Fayrer raises the question as to whether this fever, so prevalent in India, is identical with the disease which might be contracted in London, New York, or Dublin, from water-closet, drain, sewer, or well. He is of the opinion that these fevers are often the same, but that more frequently they are not, and that in hot, malarious countries climatic causes give rise to fevers identical with the others, except that they can not be traced to filth or other specific cause. But, while recognizing that but little is known of the nature of epidemics of this class, he asserts that the past twenty years show great progress in ability to successfully cope with them. He says, "Science that has enabled us to reduce the death-rate among our troops from 17·9 to 8·56 per 1,000 in Europe, and from 69 to 17·62 per 1,000 in India, speaks for itself, and, were there no other results, this alone is a triumph such as has not been achieved by other departments of knowledge." As a result of better sanitary conditions among European troops the following alteration in the death-rate is shown: from 1861 to 1865, 9·02 per 1,000; 1865 to 1870, 6·98; 1870 to 1875, 3·23; 1875 to 1876, 2·3; 1876 to 1877, ·84. In allusion to the history and treatment of cholera the doctor says: "All serves to show that it is the same now as formerly, and that, though we have gained much knowledge of its natural history of late years, yet we are as ignorant as our predecessors of its real nature. We have, thanks to sanitary measures, disarmed it of some of its terrors, and have diminished the mortality it caused; but as to treatment we have gained but little, though the empiricism of to-day is more scientific than it was in former days. We do not now burn our patients on the soles of the feet, tie ligatures round their limbs, or have recourse to other senseless barbarities; for we find that simpler and more rational methods are of greater avail, more or less according to the period of the epidemic attack, and the promptitude with which the remedies are applied. But we have learned that local causes have a potent influence, and that cleanliness, good air, pure water, and free ventilation, are all powerful opponents of cholera."

Danger of the Hypodermic Use of Morphia.—The danger of using morphia in hypodermic injections has been again forced into notice by the recent death of the Italian Consul at Bombay, India. His physician had prescribed two "grana" of morphia as a remedy for a pain in his leg from which he was suffering. The chemist mistook the word "grana" for "grammes" and gave fifteen times as much morphia as was intended. The mistake was discovered at once and remedies were applied, but the patient sank rapidly and died the same evening. The peculiar risks of the hypodermic use of morphia arise from the facts that an overdose once administered can not be recalled, and that no means exist of ascertaining how large a dose the patient can bear. An excessive quantity of morphia given by the mouth may be removed if the accident is discovered immediately, but the only resource in case of excessive injection lies in antidotes, the operation of which is very uncertain. According to the collection of facts on this subject which has been published by Dr. Kane, of this city, the smallest single dose which has appeared to have alone been the cause of death was a quarter of a grain. In a case in which death apparently resulted from the administration of a twelfth of a grain by the skin, a quarter of a grain had previously been given by the mouth. In three of the cases cited by Dr. Kane, including one in which a quarter of a grain caused death, the patients were suffering from delirium tremens; in the majority of the cases the fatal effect was due to the repetition of the hypodermic injection, or to its employment after a fair dose of opium had been given by the mouth. It is impossible to predict, or to estimate with any approach to safety, what the effect of an injection will be. Tolerance of opium by the mouth does not prove that it will be tolerated equally well by the skin; and tolerance of morphia by hypodermic injection at one time is no ground for inferring that at another time the same dose would be equally well borne. The use of morphia is peculiarly dangerous in certain morbid states, foremost among which is alcoholism. The existence of chronic Bright's disease increases the danger, as does also the existence of disease of the heart or lungs, interfering with circulation and respiration. The fact also seems to be established that the existence of severe pain does not render large doses better borne. Atropine is capable to some extent of counteracting the influence of morphia, but can not be relied upon alone. It needs to be supplemented by other remedies, and is assisted by the hypodermic injection of strychnia. It also will kill, and should not be used in a larger proportion than one twenty-fifth of a grain of atropine to every grain of morphia. Strychnia should not be used in a larger total quantity than one twentieth of a grain, and a much smaller dose should be first administered. Artificial respiration, electricity, and coffee or caffeine, remedies in common use, may also be necessary in addition. Whenever there is reason to think that the injection has been directly into a vein, the circulation in the limb should be arrested by a ligature above the place of injection; and the "Lancet" suggests that it is possible, when the fact of an overdose is at once discovered, that something may be done by local treatment to arrest absorption. The whole of the morphia can hardly be taken up instantaneously, and it is probable that, if a ligature were at once placed on the limb, an incision made through the skin at the seat of the injection, and the part freely washed, or even freely cauterized, the amount of morphia absorbed might be reduced to so small a degree that it would be possible to antagonize it, and thus save the patient's life.

Sanitary Perils at Watering-Places.—The "Lancet" has uttered a warning against the sanitary dangers to which populous health resorts are liable, which receives support from several incidents that have happened within a few years past. It is incumbent upon every one who goes to the seaside, to take care that he does not leave a comparatively healthy home to seek recreation in a place which may be a nursery of disease. Watering-places are peculiarly liable to have two kinds of perils: to the danger that infection may be brought to them by visitors, and to the risks that may arise from the insufficiency of their sanitary arrangements to meet the demands that are made upon them by the accession of large crowds. It has sometimes happened that, as soon as a child has become convalescent from an infectious disease, it has been hurried off to the seaside, and been received at lodgings without question. The sanitary precautions now carried out at many places make this a matter of more difficulty than formerly, but the danger is still hardly diminished that arises from sending off the unaffected members of an affected family to the seaside as soon as contagious disease breaks out. The "Lancet" tells of a case as having come under its own notice, in which, when a child was taken ill with a sore-throat of a suspicious character, another child in the family was sent to the seaside, was taken ill with diphtheria on the day after his arrival, and communicated the disease to other children with whom he had played. When disease breaks out in the height of the season, the fact is apt to be concealed as long as possible, and unknowing visitors continue to go down as into a trap. "Not long ago," again says the "Lancet," "family after family went down to one of our [English] largest seaside towns, to be infected with scarlet fever, the existence of which at the place was carefully concealed." The dangers arising from imperfect sanitary arrangements at these resorts and in the lodging-houses have been much discussed of late, but the agitation ought to be kept up without intermission till they are all remedied. The question of drainage, which is a difficult one anywhere, is no less difficult at seaside resorts than at other places. The most natural measure is to carry the sewage to the nearest and most convenient spot at which it can pass into the sea, and this is often the place where visitors and loungers will be most exposed to its emanations. The case is still worse on lakes, for there the slowly moving water becomes charged with sewage; and cases of illness have been known to arise from boating in the neighborhood of the discharge-pipes. Many physicians have had experience with diseases arising from filth that have been contracted at the seaside, and cases of typhoid fever originating in such places have been noticed in England as well as in the United States. That sickness is not more general is doubtless due to the fact that visitors spend so much time in the open air. If they lived there as they do at home, they would, perhaps, find many of these places the reverse of "health resorts."

Rhythmic and Colored Lights for Lighthouses.—Sir William Thomson urges a threefold reform in the British lighthouse system, viz.: "A greater quickening of nearly all revolving lights; the application of a group of dot-dash eclipses to every fixed light; and the abolition of color as a distinction of lighthouse-lights, except for showing dangers and channels and ports by red and white and green sectors." He observes that, in revolving lights of which the period is ten seconds or less and the time of extinction seven seconds or less, the place of the light is not practically lost in the short intervals of darkness, the eye sweeping deliberately along the horizon to "pick up the light, passes over less than the breadth of its own field of view in the period of the light, and thus picks it up almost as surely and quickly as if it were a fixed light. Compass-bearings may also be taken with these quick-revolving lights almost as easily and accurately as if the light were continuous. The distinction by color alone ought to be prohibited for all lighthouse-lights, on account of its liability to confusion with ships' and steamers' side-lights. In place of color, Sir William would distinguish every fixed light by a rapid group of two or three dot-dash eclipses, the shorter, or dot, of about half a second duration, and the dash three times as long as the dot, with intervals of light of about half a second between the eclipses of the group, and of five or six seconds between the groups, so that in no case should the period be more than ten or twelve seconds. The Holywood Bank Light, Belfast Lough, until 1874 was inclosed in a red-glass lantern, was only visible for five miles, and was constantly liable to be taken for a sailing vessel's port-side light. In 187-1 the red glass was removed, and the light was marked by a dot, dot, dash (. . —, or letter U of the Morse flashing alphabet), repeated every ten or twelve seconds, and has been so ever since. It is now recognized with certainty as soon as seen in ordinary weather from the mouth of the Lough, ten miles off, and has proved most serviceable as a leading light for ships bound for Belfast or entering the Lough. Sir William Thomson's objection to colored lights is corroborated by Mr. J. P. Thompson, who relates, in a letter published in "Nature," how he narrowly escaped shipwreck off the Cornish coast by inability to perceive the red flashes of the "Wolf" light, which seemed to have been neutralized by the fog, or from the daze caused by the phosphorescence of the sea.

A Singular Root-Growth.—A correspondent of "Die Natur" describes a singular form of growth of fibrous roots, which he and his associates observed in opening one of the ancient-burial places, called cromlechs, at a town in the province of Posen, Prussia. Along with other objects usually found in such burial-places, they noticed several urns, filled with ashes, calcined bones, and sand, and all closed with a cover shaped like a basin, and fitting tightly over the rim of the urn. They took off the covers and emptied the vessels, when they were astonished to find that the surface of the sand in one of them was apparently covered with a deep-black peruke, ornamented with pearls of about the size of a pea. A more careful examination showed them that this curiously discovered "head-dress" was composed of the fibrous roots of the horse-tail rush, which grew abundantly on the top of the hill in which the graves had been made. The roots of the plant having penetrated the soil to the depth of three feet and a half, had made their way through the narrow crevices between the stones of the grave, had found the urns, had then pushed up perpendicularly through the minute space between the rim of the cover and the neck of the urn, and had arranged themselves within the urn into a regular network. After the formation had been dried, the course which the principal root had taken could be traced. The fibrous roots had branched out from it, and covered the whole surface of the sand in such a manner as to deceive the observers for a time with the resemblance to a beautiful head-dress. The knots, which were taken for pearls, were irregularly distributed, and were manifestly thicker in places-in the principal root. The formation affords an interesting illustration of the faculty which the roots of plants possess of seeking for and reaching the most suitable nourishment. The operation in the present instance involved a reversal of the common direction of the growth of roots, and that which resembled an effort to reach hidden food. The case furnishes a curious parallel to the one which was described in this country a few years ago, in which the root of an apple-tree, which grew over the grave of Roger Williams, was found to have taken the place and shape of the body buried below.

Artesian Wells on our Western Plains.—A proposition to make an appropriation of fifty thousand dollars for the purpose of sinking experimental artesian wells in the Western Plains, has been advocated in Congress, and has been mentioned favorably in the press. It is urged in behalf of the scheme that of about nine hundred million acres of arid lands in Arizona, Dakota, Idaho, Montana, New Mexico, Utah, Wyoming, Colorado, and Nevada, which must remain practically a desert unless some method is found to supply them with water, about five hundred million acres of plain and valley lands would be susceptible of profitable cultivation if they could be watered. Of this, not more than three per cent, can be irrigated by the use of existing streams and rivers. It has been demonstrated, wherever settlement has been made and irrigation applied, that the lands when watered are as good as any; and the operations of the French in Algeria, which are still continued, give an encouraging promise of what can be accomplished with artesian wells.

African Fetich-Worship and Witchcraft.—Dr. Buchholz, a German entomologist, in his account of his wanderings in west Africa, notices many of the peculiar customs of the negroes of Upper Guinea, particularly those relating to fetich-worship and witchcraft. While among the Akkra tribes of the Gold Coast, he found that fetiches, generally clay dolls representing a man and a woman, had been laid at the foot of the termite-hills which he was interested in examining, with offerings around them. The fetich-processions are celebrated with considerable pomp, in which the fetich-drum, a stick provided with rings on which a little hollow ball, a gourd-shell, is rapidly struck, plays an important part. At the village of Abreri, farther inland, the ceremonies were held in a large, open place, at one end of which silvered images of the gods, rude figures representing a bird, a turtle, an ear of corn, and a figure holding different vessels, were set up in an orderly manner on a pillar, while the priest performed his ritual at the other end. The music, of drums, bells, and other instruments, including a drum of bronze, was accompanied by the multitude with a rhythmical hand-clapping. At the feast of the new moon, in addition to the music and the singing, each participant had a white streak drawn over his face, and the master of ceremonies, swinging a peculiar brush and gesticulating frantically, had his face painted all over white. The Bakhniri believe, when any one dies or is sick, that he has been bewitched; or if death is caused by a snake, or a crocodile, or a leopard, that the animal has been bewitched to cause it. The person accused of witchcraft is compelled to drink a decoction of a poisonous wood called sassha-wood; if he vomits up the drink, he is considered not guilty and let go; otherwise, he is killed if he does not die of the poison. They have a great fear of white people and all that comes from them, and especially regard paper that has been written upon as a fetich and the place or the thing on which it falls as taboo. When Dr. Buchholz on one occasion dressed the wounds of a sick person, he let a little piece of paper fall out of his pocket without noticing it. When he next went to visit the sick man, he found that his patient had been quarantined because the house was considered bewitched, and the piece of paper was ceremoniously handed back to him. One day, when a woman was to be buried, the negroes sent a messenger to him with a special request that he would not leave any pieces of paper anywhere that he went, because, if he did, they would have to keep away from those roads and places. A son of old King William, of Bimbia, having died after a long sickness, an innocent man was accused of having caused his death by witchcraft. He was taken out and hung; immediately the whole population, men, women, and children, ran to the shore, stripped off the little they had on, and went into the water to wash off whatever enchantment might be on them. One of the festivals among the Deialla negroes was diversified by an exhibition of single combat. The champion who achieved the most brilliant victory was hailed with great applause, and his mother sung and danced to his honor; but one of the defeated ones went up to his mother and reproached her because she had not given birth to a stronger son.

A Remarkable Coal-Mine Explosion.—M. A. Delesse gives in "La Nature" an account of an explosion of carbonic acid which took place in a coal-mine at Rochebelle, France, on the 28th of July, 1879. Two workmen, who were at the bottom of a shaft about three hundred and seventy-five yards deep, heard a sudden detonation, which was followed in about a minute by another louder one. Their lamps were instantly put out; they felt a faintness, and were barely able to escape to the hoist-car and be drawn out. Three other miners, who were working in a gallery ninety yards higher, were suffocated. The scene of the disaster was afterward examined, and it was decided that the explosions could not have proceeded from carburetted hydrogen, for they were not accompanied by flames; thin partitions in the shaft and upper galleries were not broken; the bodies and clothes of the dead men showed no signs of having been burned; and powder which lay in the gallery and in cartridges had not taken fire. No signs of carburetted hydrogen had ever been observed about the mine, but carbonic acid had always been present, sometimes in such quantities as to compel the men to cease work, and a ventilating apparatus had been put up to discharge it. The explosion was found to have taken place in front of the excavations in one of the upper galleries (two hundred and sixty-six yards below the surface), which was obstructed for a considerable distance by the broken coal. Small particles and dust were thrown out to a much greater distance, and the man who was working in front had been thrown back and buried under the fragments. About seventy-six tons of coal appear to have been displaced by the explosion. Carbonic acid continued to escape from the coal after the accident, and even the pieces that had been thrown into the gallery gave it out when they were disturbed. No satisfactory explanation has been offered of the manner in which the gas could have accumulated, and have gained so high a pressure as to cause a detonating explosion. The gas, it is suggested, may have been formed by the action of the sulphuric acid which escapes from a vein of rapidly oxidizing iron pyrites in the neighborhood upon an adjoining bed of limestone, but this leaves the question of a violent explosion still unsolved.

A Systematic Investigation of Earthquakes.—The Swiss Natural History Society has appointed a special commission of seven members for the systematic observation of earthquakes. Recognizing that a large number of observations at as many places as possible is necessary for the sufficient investigation of every earthquake, the commission has taken measures to enlist those persons generally in its own country who are interested in investigations of this kind in coöperation with its work, and is perfecting a special organization for the collection of observations with the aid of such assistants. A special field is assigned to each member of the commission, and he is expected to put himself in communication with persons who may be disposed and competent to aid him in different parts of his district. A tract for distribution has been published under the direction of the commission, which contains a summary of the most recent facts that have been ascertained about earthquakes, and points out the directions in which an increase of knowledge on the subject can be promoted. A number of stations, selected by the commission, are provided with instruments for special observations. The observers are furnished with a schedule of questions respecting the different phases of the earthquakes they may witness, which they are expected to answer as fully as they are able to do. They are also requested to represent the phases of the shock graphically on a chart, where it is possible, to assist in comprehending and reviewing the character of the phenomena. The collected accounts of observations are arranged and preserved in an archive of earthquakes. As the questions concern a subject of general interest, and are useful aids to investigation everywhere, we repeat them entire. They are seventeen in number, as follows: 1. On what day was the earthquake noticed? 2. At what hour? 3. How did your clock agree on the day, or, better, on the hour, of the earthquake, with the nearest telegraph clock? 4. Endeavor to furnish an exact description of the place of observation, the canton, town, situation, whether in the. open or among buildings, in what story of the house; state in what position and what occupation the observer was when the shock was perceived? 5. On what kind of soil does the place of observation stand? Whether the surface be of rock, soil, or peat; depth of the ground to bed-rock, etc.? 6. How many shocks were felt, and during what interval of time? 7. In what direction was the motion? Did it come from below, was it short and in a direction from side to side, or broad, surging in the form of waves, or only a trembling? In case there were more than one shock, was there a difference in the character of the different shocks? With what could the motion be compared, and how did it affect the observer? 8. In what direction was the trembling of the earth felt? 9. How long did the shocks and the subsequent trembling seem to last? 10. What effects did the shaking produce? 11. How might this earthquake be distinguished from others which have previously been noticed by the same observers? 12. Was any noise heard, and, if so, what kind of a noise was it—like thunder, a clinking, a rattling, a clap, or a continuous noise, etc.? 13. Did the noise precede the shaking or follow it, and how long did it last in comparison with the duration of the shocks and of the intervals between them? 14. What particular minor phenomena were observed? Were there, for instance, anything peculiar in the behavior of animals; any drying up, or troubling, or breaking out again of springs; any peculiar rustling in the woods, any gusts of wind simultaneous with the shocks, or abnormal features of the weather? 15. What was noticed with regard to the lakes? 16. Were lighter shocks felt before or after the main shocks, and at what time? 17. Can you mention any other observations made by your acquaintances or in your neighborhood, or can you give the addresses of persons who are able to answer all of these questions, or a part of them?

Precocity a Sign of Inferiority.—M. G. Delaunay, in a communication to the French Société de Biologie, has advanced the opinion that precocity is a sign of biological inferiority. In support of his position he adduces the fact that the lower species develop more rapidly, and are at the same time more precocious, than those higher in the scale. Man is the longest of all in arriving at maturity; and the inferior races of men are more precocious than the superior, as is seen in the children of the Esquimaux, negroes, Cochin-Chinese, Japanese, Arabs, etc., who are, up to a certain age, more vigorous and more intellectual than small Europeans. Precociousness becomes less and less in proportion to the advance made by any race in civilization—a fact which is illustrated by the lowering of the standard for recruits, which has been made necessary in France twice during the present century, by the decreasing rapidity of growth of the youth of the country. Women are more precocious than men, and in all domestic animals the female is formed sooner than the male. From eight to twelve years of age, a girl gains one pound a year on a boy, and in mixed schools girls obtain the first places up to the age of twelve. The inferior tissues and organs develop before the higher ones, and the brain is the slowest of all organs to develop. M. Delaunay concludes his paper by stating that the precocity of organs and organisms is in an inverse ratio to the extent of their evolution.