Popular Science Monthly/Volume 45/May 1894/Popular Miscellany
Reptilian and Amphibian Motions. — M. Marey has extended his time-photographic studies of locomotion to mammals, birds, reptiles, fishes, and articulates. The processes are rather difficult, because they have to be applied to a great variety of movements, and of methods and habits of carrying them on; but it is nearly always possible to assure satisfactory representations by adapting the methods of working to the conditions. The chief difficulty is in getting the animal experimented upon to go at its ordinary gait. This is much more easily accomplished with domesticated animals than with wild ones. By comparing the types which he has got represented, M. Marey discovered some very interesting analogies. Thus, in locomotion on land and on water, he was able to follow the gradual transition between simple "reptation" and the most complicated kinds of locomotion. An eel and a viper, put in water, advance in the same manner; a wave with lateral inflections runs continuously from the head to the tail of the animal, and the velocity of the retrograde movement of the wave is much greater than the speed of translation of the animal. If the animals are set upon the ground, the mode of reptation will be modified in both in the same way. The amplitude of the undulatory movement from one side to the other will be greater, and will increase as the surface on which the animal creeps is smoother. A vestige, more or less pronounced, of the undulatory reptilian movement remains with fish that have fins and reptiles endowed with legs. In the sea-dog, for instance, the retrograde wave running along the whole body is very pronounced. It is considerably reduced in the salmonides, and does not appear except at the tail in fishes the bodies of which are more stubby. This retrograde wave is plainly manifest in the gecko, but less so in some other lizards. The analysis of the varieties of locomotion of the batrachians in the different stages of their evolution is very interesting. The tadpole, for example, exhibits in its earliest stage progression by the undulation of the caudal fin; a mixed type of locomotion comes in with the paws; the tail continues to wriggle, and the hinder limbs make the swimming motions appropriate to them; and the latter movements exist alone for some time after the tail has disappeared. These motions, which so much resemble those of man's swimming, present the peculiarity of the fore legs having no part in them, and of the hind legs, after having been separated so widely as to form a right angle with the axis of the body, approaching one another till they become parallel, then bending and spreading out again to begin a new spring. The motions of lizards' legs are so swift as to escape direct observation, but the successive movements of the fore and hind limbs can be followed in photographs taken forty or fifty times a second. The normal gait of the lizard and the gecko is the trot — that is, their limbs move diagonally. The great amplitude of the motions, combined with the undulation of the axis of the body, causes the limbs on the same side to come very near one another, and then separate widely in the following instant. The lizard projects its hind foot nearly into its armpit on the side on which the body becomes concave; an instant afterward that side becomes convex, the fore leg is carried far forward, and, the body forming a convex arc on that POPULAR MISCELLANY.
��side, the two limbs are widely separated. Interesting observations have also been made of the motions of insects, arachnids, etc.
Modern Survivals of Primitive Saper- stitions. The recently published book of S. Baring-Gould on Strange Survivals fur- nishes curious suggestions concerning the origin and primary meaning of many cus- toms and practices that have come down to us from remote ages, and which we observe or remark upon without a suspicion of their significance. The superstition has gone out of vogue in civilized lands that the saci'ifice of a human being in its foundations is neces- sary to the staliility of any important build- ing. But King Theebaw, of Burmah, in our own days, obeyed it ; and the feeling remains among the superstitious in Europe that some unseen power must be propitiated, or it will some time and somehow exact its dues ; and numerous legends prevail with reference to gi'and structures of how the mysterious pow- ers were propitiated in the beginning, or ex- acted an equivalent for the neglected sacri- fice. Only fifty years ago the people of Halle are said to have tried to persuade the builder of a bridge to immure a child in the foundations in order to insure the stability of the piei's. The designs of gable ends, carved ridge-tiles, representations of ani- mals, such as horses and horsemen, and the stone balls with which houses are adorned, all have meanings. The completion of a building was signalized by a sacrifice origi- nally, just as the laying of the foundations was. Horses were held to be sacred by the Northern i-aces, and formed, next to a man, the worthiest sacrifice ; and if a horse's skull was not put on the point of a gable, a horse's head was carved. At a chieftain's death, his horse was buried with him ; and to-day the charger of an officer follows his coffin to the grave. Poles, sui-mounted by branches of leaves and flowers, protect the farmhouses of the Black Forest from hghtning, and rep- resent the ancient oblation of a bunch of grain to Odin's horse; and gables often have carvings connected with this oblation to Odin. At Yuletide oats are thrown out for Santa Claus's horse (the colt of Odin having been transferred to Santa Claus), and a person convalescent after a dangerous ill- ness is said to have " given a feed to Death's
��horse." The sheaf of corn that is fastened to the gable in Norway and Denmark now an offering to the birds was originally a feed for Odin's horse. Formerly, the last bundle of oats in a field was cast into the air by the reapers, -for Odin at Yule to feed his horse ; and a similar custom prevailed in Devonshire, in Mr. Baring-Gould's recollec- tion. The mediccval habit of affixing the heads of criminals to spikes on battlements was the survival of the offering of skulls to Woden, and the stone balls on the gables of manor houses and on lodge gates are the sur- vival of the right of life and death possessed by the lords of the manor.
"State Socialism" in New Zealand.
At a recent meeting of the Royal Colonial. Institute of Great Britain the Earl of Onslow described some experiments in what was called state socialism that had been under- taken in New Zealand. The Government had expended large sums in providing water for mining purposes for working miners, and had given the men the task of repairing the water works, remunerating them, not in money, but in orders for water for the pur- pose of getting gold. It had worked a sys- tem of settling men upon land, with advances of money for house-building and cultivation. In a visit to two of these settlements one formed by voluntary association, and the other from the unemployed the speaker had found the voluntary association prosperous, while the unemployed were calling upon the Government to take them out of " the hole " they had been brought into ; and he formed the opinion that, while the Government was not in any case without ample security for its advances, yet only careful selection of the land and of the men would secure success. The colony had acquired by purchase, at the owner's valuation, the largest estate in the coimtry, and opened it for settlement; and he believed that, so long as it did not unduly saddle the colony with debt, this experiment in the resumption of the national estate would be likely to prove satisfactory to the Government. The labor department in New Zealand had been more successful than the one abolished last May in Victoria, because numerous country branches had been created instead of calling all the workmen to the central office in the capital. In the system
�� � 138
��THE POPULAR SCIENCE MONTHLY.
��of co-operation on Government work, the men form themselves into gang?, the strong with the strong and the weak with the weak, so that the weak, although they could not execute work rapidly, were yet not altogether excluded from employment. Two interesting results of the experiment of introducing labor leaders into the Government were noted ; when intrusted with power, they became im- bued with a sense of responsibility, and could successfully resist the establishment of state charity in the guise of work or unprofitable undertakings, and members of a revising chamber, drawn from whatever party, would resist measures which they believed not to be the deliberate will of the people.
Succession of Arctic Seasons. In his
presidential address before the Geographical Section of the British Association, Mr. Henry Seebohm gave a graphic description, largely drawn from personal experience, of the suc- cession of the seasons in the high arctic lati- tudes. He said that the stealthy approach of winter on the confines of the polar basin is in strong contrast to the catastrophe which accompanies the sudden onrush of summer. One by one the flowers fade and go to seed, if they have been fortunate enough to attract by their brilliancy a bee or other suitable pollen-bearing visitor. The birds gradually collect into flocks, and prepare to wing their way to southern climes. The date upon which winter resumes its sway varies greatly in different localities, and probably the mar- gin between an early and a late winter is considerable. The arrival of summer hap- pens so late that the inexperienced traveler may be excused for sometimes doubting whether it really is coming at all. When continuous night has become continuous day without any perceptible approach to spring, an Alpine traveler naturally asks whether he has not reached the limit of perpetual snow. It is true that here and there a few bare patches are to be found on the steepest slopes, especially if they have a southern ex- posure. It is also true that small flocks of little birds may be observed flitting from one of these bare places to another; but their appearance does not give the same con- fidence in the arrival of summer to the arctic naturalist as the arrival of the swallow or the cuckoo does to his brethren in the sub-
��arctic and subtropic climates. The birds seen are only gypsy migrants that are perpetually flitting to and fro on the confines of the frost, continually being driven south by snow- storms, but ever ready to take advantage of the slightest thaw to press northward again to their favorite arctic home. The gradual rise in the level of the river inspires no more confidence in the final melting away of the snow and the disruption of the ice which supports it. In Siberia the rivers are so enormous that a rise of five or six feet is scarcely perceptible. During the summer which the author spent in the valley of the Yenisei there were six feet of snow on the ground. To all intents and purposes it was midwinter, illuminated for the nonce with what amounted to continuous daylight. Dur- ing May there were a few signs of the pos- sibility of some mitigation of the rigors of winter, but these were followed by frost. At last, when the final victory of summer looked most hopeless, a change took place ; the wind turned to the south, the sun retired behind the clouds, mists obscured the land- scape, and the snow melted " like butter upon hot toast. . . . The effect on the great river was magical. Its thick armor of ice cracked with a loud noise like the rattling of thunder, every twenty-four hours it was lifted up a fathom above its former level, broken up, first into ice-floes and then into pack-ice, and marched down stream at least a hundred miles. Even at this great speed it was more than a fortnight before the last straggling ice-blocks passed our post of observation on the Arctic Circle ; but during that time the river had risen seventy feet above its winter level, although it was three miles wide, and we were in the middle of a blazing hot sum- mer, picking flowers of a hundred different kinds, and feasting upon wild ducks' eggs of various species. Birds abounded to an in- credible extent."
Analysis of Volcanic Ashes. An analysis has been made by M. A. F. Nogues of the ashes and volcanic sands thro^vn up by the volcano Calbuco, in Chili, during an eruption which began in February, 1893, and had not ceased in December. The fine dust products were projected to places as far off as Moutt, Valdivia, and La Union, at distances varying from twenty-five to one hundred and twelve
�� � POPULAR MISCELLANY.
��miles. They contained no vitreous grains, but simply the minerals that constitute the andesites of which the mass of the mountain is composed, and in the same state as in them. The andesite of the prehistoric erup- tions of the region when reduced to powder and traversed by the vapor of water gave the same products as the ashes cast out in 1893 by the volcano. These ashes, therefore, appear to have been derived from the tritu- ration and pulverization of the old lavas of the region without their having been re- melted. The author remarks that the erup- tion of Calbuco has given out such consider- able quantities of watery vapor that the usual atmospheric conditions have been ma- terially modified by it. Rains are abnor- mally abundant even in central and northern Chili, with snows on the mountain chains and the sky covered with clouds conditions very different from those which normally prevail in the country.
Children's Letters. The characteristics of children's letters ai-e pertinently described in the London Spectator, which says that the writers " come straight to the point, and get down with it, with a unanimous contempt for self-advertisement, which shows that the dislike to be ' drawn ' on matters nearly af- fecting themselves, which is common to the oldest and wisest of mankind, is fuKy shown by their youngers and betters. The cliild is, in this, the father of the wise man. Not that they refuse information. The bare facts are always at the service of the public. They fall into ' common form,' and in a score of letters written by very young children it is difficult to find one in which the decorous reticence as to self is exceeded. Their age, very accurately stated ; the number of their brothers and sisters, among whom the last baby naturally takes a leading place; and, possibly, a description of their home, limited, as far as possible, to the information given in their postal address, is evidently consid- ered to be sufficient data from which to form an idea of themselves and their surround- ings. Then, in nearly every case, follows a list of the household pets. Judged by the evidence of children, the dog is in every case the most important personage, next to the baby, in the estimation of the nursery. His size, accomplishments, and benevolence, his
��good or bad temper, and in every case his name, are given with a conscientious and personal interest which is accorded to no other animal. Apparently, there is no limit to the number of pets which the fathers and mothers of our race, whether English, Ameri- can, or Anglo-Indian, set to the fancies of their children. . . . Looking through a pile of letters from children, mostly girls of all ages fi'om four to thirteen, the writer finds nearly three quarters devoted to careful ac- counts of dogs, tame mice, a donkey, ' Joey,' a ' ginipig,' ' rabits,' chickens, goats, and in- numerable pigeons. There is hardly a word about themselves or their feelings in the whole collection, though the health, wants, and probable sentiments of the animals are treated at great length and with every diver- sity of spelling. Lists of ' what the pigeons have got ' such as ' the f antail,' two babies and one egg ; the ' Jocobin, two eggs,' etc. are followed by other lists of ' ones that have got nobody.' Chickens are counted before they are hatched and after; and terrible descriptions of the results of a cock-tight, which has made one of the combatants ' all bloddy,' are given at great length, with ac- counts of the illness, treatment, and burial of other creatures. Events, such as games, parties, or expeditions, are, as a rule, only mentioned, without comment."
Photography of Colors. The process of photography of colors, discovered a few years ago by M. Lippmann, has been con- siderably improved, and has now been brought to such a degree of perfection that with it the composite colors of natural ob- jects, such as flags, flowers, and fruits, a multicolored parrot, and a window with four colors, are photographically reproduced. Li the hands of M. M. Lumiere it has been applied successfully to chromolitho- graphs, natural landscapes, and portraits. The time of exposure required has been re- duced from thirty minutes a few months ago to from three to five minutes. While so much has been accomplished in this art, many requirements remain to be fulfilled : the time of exposure to be further reduced; accurate isochromatic plates to be obtained, and a way found of taking proofs on paper. The colored proofs have the property of the old-fashioned daguerreotypes, of not being
�� � 140
THE POPULAR SCIENCE MONTHLY
clearly visible except when viewed at the right angle. This property, however, has the great advantage that it makes retouching of the picture impossible. To remedy the in- convenience arising from it, M. Lippmann has devised an apparatus for viewing the pictures by the aid of which the proper con- ditions of the angle can always be obtained.
Toads and Cancers. Toads were used during the last century as local applications for the cure of cancerous breasts. An ac- count of a cure said to have been wrought by this means is given in Martin's Natural History, pubHshed in 1785, from a letter from a physician to the Bishop of Carlisle. The doctor had attended the operation for eighteen or twenty days, and was surprised at the result. The toad was put into a linen bag, all but the head, and that was held to the part. It was supposed to suck the poison till it swelled up and died. Then other toads were put on, and so, till the sore was cured. Sometimes they disgorged, recov- ered, and became lively again. Other au- thorities, the writer said, held that the toads did not suck the poison, although they ad- mitted that the swelling and falling off dead was a general consequence of the applica- tion. Dr. Leonard G. Guthrie shows, in the Lancet, that a toad can not suck, but when injured or alarmed blows itself up to about twice its ordinary size, and when held and constrained for any length of time in a hot hand, sweats profusely and would pi-obably soon die. The efPect of the secretion when held on the hand is to cause dryness, numb- ness, and a tingling ; which it probably did to the cancerous breast, giving a sort of re- lief to the pain.
A "Sanitary" Bnilding. Dr. W. Van
der Heyden, of Yokohama, Japan, has de- signed a sanitary building, in which he seeks in winter to imprison the heat-rays of the sun, and in summer to admit the light while excluding the excess of heat; and at the same time to afford perfect ventilation and security against disease germs. The walls of the houses are made of air-tight boxes with sides formed of panes of glass, built upon one another, hermetically jointed with felt, and filled with a solution of alum ; the roof is covered with cement. "A house built in
such a way is an entirely closed hollow space, like a box itself, without windows or doors no openings, and no fissures. It is practically impermeable to air, moisture, heat, cold, dust, microbes, and insects." At convenient in- tervals in the walls of rough plate glass are plates of polished glass, to be used as win- dows for looking out. "Doors are not wanted, because the entrance can be made through the floor by means of a lift or stair- case from an underground room which re- ceives no direct light from the sun. The walls of the underground room are made of ordinary bricks, plastered inside, and pro- tected outside with a thick layer of clay to keep out moisture ; it will be better to have these walls constructed with iron plates, as quick conduction of heat is the requisite here. The light for this room comes through glass boxes let in the four corners of its ceiling which forms the floor of the upper room. . . . There is a nice mild diffused light in the lower room which fully enables one to do any laboratory work, and is suffi- cient to read by." The walls are protected against freezing in winter by inclosing the whole building in a covering of window glass. In the summer the window-glass frames are put within the house, and furnish air cush- ions, still further preventing the accession of outside heat. Special arrangements are made for the renewal of air, heated in winter and sterilized at all times ; and as the house is proof against the entrance of air from any other source, all microbes, disease germs, in- fections, and insects are efficiently kept out. The author has tried his house, and thinks well of it.
Temperature of the Interior of Trees.
The experiments of M. Prinz on the varia- tions of temperature in the interior of trees seem to show that the sap contains large quantities of gas, which escapes with a sound often quite marked, and which can some- times be heard two steps away. The mean annual temperature of the interior of a tree corresponds with that of the external air ; but the monthly mean sometimes varies by two or three degrees. It usually requires about a day for a fluctuation of temperature to be transmitted to the heart of a tree. While the difference between the interior temperature of a tree and that of the air is POPULAR MISCELLANY.
��usually only a few degrees, it is sometimes as much as ten degrees ; when the temperature of the air falls below the freezing point and continues to fall, the internal temperatuie of a tree descends to a point near that where wa- ter of vegetation freezes and continues there stationary. Water of vegetation freezes a few tenths of a degree below the freezing point of water. The absolute maximum in the in- terior temperature of a tree trunk may be produced a considerable time before the maximum of the surrounding air, in conse- quence of the direct action of the spring sun and air on the leafless trees. During the high summer heats the internal temperature of trees is nearly steady at about 15 C, with a variation of two degrees or more, even under exceptional conditions of variation in the temperature of the air. A large tree is usually a little warmer than the air in the cold months, and a little cooler than the air in the warm months.
Anatomy and Physiology for Young Men.
Writing to the projectors of the Quarter- Century testimonial book to Prof. Burt G. Wilder, Dr. Andrew D. White refers to one point on which Prof. Wilder in the early days was able to render a special service out- side of his chosen field. " While the uni- versity was in its earliest beginnings, a sort of nebulous state, I was impressed by a re- mark by Herbert Spencer, in his book on Evolution, as regards the relative values of different kinds of knowledge. He named, among the things to be taught to young men, human anatomy and physiology ; and his arguments seem to me now to be absolutely conclusive. For apart from the practical part of these studies, they seem to form a most stimulating beginning to study in natu- ral history generally, not perhaps the logical beginning but the best practical beginning, as is shown by the fact that in all ages the great majority of students of note in natural science have been physicians. Under the in- fluence of this impression I asked Prof. Wil- der to give a course of lectures every year to the freshman class on anatomy and physi- ology. Various arguments might have been used against this ; it would have been said that, later in their course, students would have been better prepared to appreciate the fine points of such lectures, and the example
��of all the older institutions might have been pointed to in which such lectures, when given at all, were generally given as a hurried course in the senior year. But the idea of making an impression in favor of studies in natural science, and especially in human anatomy and physiology, just when young men were most awake to receive them, carried the day with me, and hence my request to Dr. Wilder. He acceded to it at once, and for several years, in fact, until the pressure of other duties drew him from this, he con- tinued these lectures, and it turned out that I had builded better than I knew ; not only did the lectures produce admirable practical results, not only did they stimulate in many young men and women a love for natural sci- ence and give them an idea of the best meth- ods in its pursuit, but they made a most happy literary impression upon the students generally ; the professor's wonderful powers of clear presentation in extemporaneous lec- tures proved to be a wonderful factor in literary as well as scientific culture. There was another theory of mine proved to be true by the professor ; for I had often felt that mere talks about literature, mere writ- ing of essays, the mere study of books of rhetoric, were as nothing in their influence on the plastic minds of students compared with lectures thoroughly good in matter and manner given in their hearing day after day. Naturally I have always felt exceedingly grateful to Prof. Wilder for proving that theory true and at the same time rendering a great service to his students and to the university."
Preparation of Collections. In his re- port of the Department of Botany and For- estry in the State Agricultural College of Michigan, Prof. W. J. Beale gives a list of the more common mistakes which young col- lectors are apt to make in preparing their col- lections, the perusal of which may give hints of the manner in which the work should be done. They are: The specimen is a mere " snip " of a thing, one little top, destitute of lower leaves, of roots, and root stalks, in- stead of enough to fill completely a whole sheet. In many instances the plant is pulled into small pieces, and runners, sterile shoots, old leaves, etc., are thrown away ; specimens lack fruit, which is often of more importance
�� � 142
��THE POPULAR SCIENCE MONTHLY.
��than are the flowers ; if tender and young, they are pressed too hard, or later in the sea- son are not pressed sufficiently to make the leaves dry flat. Too many use newspapers for the light sheets on the driers. The printed letters were made with oil, and such spots can take up little moisture. Plants are put in driers which are not thoroughly dried by the heat of the stove or the direct rays of the sun. The old-fashioned press made of tight boards is a clumsy device, but still in use. Plants are not changed two or three times a day on the start, and all this time kept in a warm place hence the color is not good ; they are too long for mounting, and must be broken or cut ofP or cut in two to fit the sheet of standard size. For the proper methods, novices are referred to cer- tain articles in botanical journals, to a chap- ter on the subject in Gray's large text-book, " or, better still, to hang about and worry some good collector and see how he does it."
Bathing after Exercise. The Lancet ob- serves that " the popular notion of the in- jurious effect of a cold bath taken by one who is overheated from exercise must pos- sess as all such ideas have some basis in experience ; and yet it is falsified by the ex- periences of athletes from the days of the Greeks and Romans even until now, who find in this procedure a refreshing and stimulat- ing tonic after the exertion they have recent- ly undergone. And, physiologically speak- ing, a cold plunge or douche taken immedi- ately after the physical effort, when the skin is acting freely and there is a sense of heat throughout the body, is as rational as in the experience of the athlete it is beneficial. It is paralleled by the tonic effect produced by the cold plunge when the skin is actively secreting after a Turkish bath, and finds its rationale doubtless in the stimulation of the nervous system, in the increase of internal circulation, and also in the renewal of ac- tivity to the cutaneous circulation after the momentary contraction of bloodvessels due to the cold. The popular belief, doubtless, rests on the injurious effects which may be induced by the bath in one who does not re- sort to it immediately, but allows time for the effects of fatigue to show themselves on the muscles and nerves and for the surface of the body to get cool. Taken then, the
��bath is more likely to depress than to stimu- late ; there is less power of reaction and greater liability to internal inflammations. At such a time a warm bath rather than a cold one is more suitable and more safe. It has been suggested, however, that the prac- tice of indulging in a bath after violent ex- ercise may initiate renal disease. Of this there is no evidence. The transitory albu- minuria observed after prolonged cold baths may indicate the disturbance in the renal circulation which ensues upon them ; but these cases are in a different category from those to which we are now alluding, nor are we aware of any facts to prove that, even in them, Bright's disease has been developed in consequence of the transient departure from the normal. Lastly, it must be I'emembered that those indulging in athletic exercises of all kinds are presumably sound in heart as well as limb, and that such persons may take with impunity and, indeed, with benefit meas- ures which would be distinctly harmful to the weakly."
Recreations for City Cliildren. Struck by the fact that the present crowding of houses in cities is unfavorable to the free ex- ercise of children in play such as prevailed when man lived iu a more scattered way, Prof. S. T. Skidmore, of Philadelphia, has sketched a scheme for the evolution of a new system of play. Even under the pre- vailing conditions, the way for the develop- ment of proper play, he beheves, is just as open as for anything else, while its develop- ment requires the genius of thought and well-directed business enterprise. The au- thor's plan rests upon the principle that " play is the exercise of the faculties as such ; the doing is for the sake of the doing. It is Nature working toward her end in the child by prompting to the free, objectless exercise of those expansile powers which he sees at work in adult life. If he sees the way open and he has the needful facilities, he will imi- tate so closely, in miniature, the activities of the age to which he belongs, that his play will not be a nuisance, so discordant as to be intolerable ; but if left entirely with his own resources, he can do nothing else than drag forward those relics of barbaric play which have descended to him by tradition- from barbaric children, who copied the simple
�� � rudenesses of their own barbaric times." So Mr. Skidmore would find his substitute in diversion derived from pursuits, achievements, and habits of the children's elders. "In an age of mechanic arts and commerce, of which the great men are inventors, authors, business organizers, engineers, and self-made millionaires, with the eyes of youth trained upon them in admiration, interested in everything that pertains to their history, and eager to imitate them, it is nonsense to suppose that the boys can not be made to belong to such an age in their play as exactly as the men do in their work." The new play must call forth the constructive faculties, and manual training is held up as an element of it.
Propagation of Cholera. — The report of the Cholera Quarantine Board at Alexandria, Egypt, after reviewing the work of contending against the epidemic last season, inquires into the origin of the disease. According to information received in Egypt, the first cases of cholera were observed among the Yemen pilgrims immediately on their arrival at Mecca. It is known that cholera must have been prevailing in the Yemen as lately as the end of 1892. Discussions on the subject in the past have usually been very unsatisfactory and the conclusions very indefinite. The serious fact remains that cholera epidemics among the pilgrims annually collected at Mecca are of very frequent occurrence and are a standing menace to Egypt and Europe. Four times within the last twelve years the disease might have been introduced by the pilgrims into Egypt or Europe, or both, and the experience of France and Spain has shown how easily it might become endemic. The endeavors of the Quarantine Board have fortunately been successful in stamping out cholera before the pilgrims reached Europe.