Popular Science Monthly/Volume 16/December 1879/Popular Miscellany
POPULAR MISCELLANY.
Physiology of the Turkish Bath.—Most accounts of the Turkish bath have been confined to general descriptions of the details of the process, and of the sensations experienced during its use; while comparatively little attention has until lately been paid to the more important consideration of its influence on the bodily functions. To supply this need, Mr. William James Fleming, M.B., Lecturer on Physiology in Glasgow, began some years since a series of careful experiments with the action of the bath on his own person. These were continued down to a recent period, and we now have the results of the investigation in the form of a valuable paper published in vol. xiii. of the "Journal of Anatomy and Physiology."
To those not acquainted with this form of bath it will be sufficient to say that the essential part of the process consists in the immersion of the body in dry air at a temperature varying from 130° to 200° Fahr. for from half an hour to an hour generally, and subsequent douching with cold water.
Mr. Fleming's experiments were all made between lunch and dinner, usually from 4 to 6 p. m., in a bath heated by Constantine's system. This is an arrangement of stoves by which a constant current of pure air is drawn from the outside atmosphere, heated by passing through a species of oven, and driven into one of the apartments of the bath with such force that it traverses the whole suite of rooms, parting with some of its heat in each, and ultimately escaping from the last into the outer air again. By this means not only the air for breathing but also that in contact with the skin is constantly renewed, so that a layer of watery vapor does not, as in all baths heated with stationary air, soon cover the body, and thus convert the bath into a vapor one. The experiments usually began with a heat of about 170° Fahr. for a few minutes, in order to produce sweating rapidly, followed by a temperature of about 130° Fahr. during the remainder of the stay in the hot rooms. This the author regards as the best practice for habitual bathers, as perspiration, being once freely established in the hottest room, is kept active by the lower degree of heat.
The investigation was specially directed to the effect produced by immersion in hot, dry air on—1. The amount of material eliminated from the body in excess of the normal; 2. The alteration produced in the temperature of the body; 3. The influence on the pulse-rate; 4. The influence on the rate of breathing; 5. The alteration in the composition of the urine; 6. The composition of the sweat; and, 7. The arterial tension as shown by the sphygmograph. The results of the investigation are presented in the form of averages representing a large number of observations.
Omitting a description of the manner in which the experiments were conducted, and also the detailed results obtained, the following are the conclusions drawn by the author from those results. It was shown—1. That a very large quantity of material can be eliminated from the body in a comparatively short time by immersion in hot, dry air; and, although the greater part of this is water, still solids are present in quantity sufficient to render this a valuable emunctory process; 2. The temperature of the body and the pulse-rate are markedly raised. The respiration falls at first, but afterward is less influenced than would be expected. The urine is increased in density, and deprived of a large portion of its chlorides, while, if anything, an increase in the amount of urea is produced. Arterial tension is increased, due probably to the rapid action of the heart and the gorged condition of the capillary circulation.
From these the following practical considerations as to the use of the Turkish bath in medicine are deduced: Its most important effect is the stimulation of the emunctory action of the skin. By this means we are enabled to wash as it were the solid and fluid tissues, and especially the blood and skin, by passing water through them from within outward to the surface of the body. Hence, in practice, one of the most essential requisites is copious draughts of water during the sweating.
The elevation of the temperature, and more especially of the pulse-rate and blood pressure, point to the necessity of caution in cases where the circulatory system is diseased.
Excessively long duration of the bath seems to produce more or less depression, as shown by the fall of the pulse and temperature after fifty-five minutes.
The great advantage of the bath seems to be the power it gives of producing a free action of the skin in persons of sedentary habit, or suffering from disease interfering with fluid excretion, and by its means probably a considerable elimination of morbid matter may also be brought about. Besides, and along with this, it is an efficient means, if resorted to sufficiently early, of relieving internal congestion.
Distribution of the Electric Light.—A recent trial, in San Francisco, of Molera's and Cebrian's system of dividing and distributing the electric light, is thus described in the San Francisco "Morning Call" of September 30th: "An exhibition of a new system of utilizing and dividing the electric light, recently discovered by Messrs. Molera and Cebrian, civil engineers, of this city, was given last night at 412 Market Street. Quite a crowd of spectators witnessed the experiments, which had a very satisfactory result. Two floors were well and uniformly lighted by the light obtained from a generator placed in one corner of the upper story of the building. The manner of thus dividing the electrical current consists of the use of a system of reflecting mirrors and lenses, which concentrate and conduct the parallel rays or beams of light by the medium of tubes to any desired distance without weakening, except in a comparatively small degree, its intensity. The main advantages claimed by the inventors for this system are, that the light may, through the agency of a diffusing lens, be distributed from a single beam throughout all the rooms of a house or hotel, and may be divided without material loss of power. The supply of light is also controlled by the reflector, and in any or all of the rooms the brilliancy of the light may be increased or diminished at will. It is further argued that the system dispenses with the necessity for regulators or lamps, that the loss consequent upon the use of electrical conductors is avoided, and that the capital invested is smaller than is required for gas-works. Heretofore the difficulty experienced by electricians has been to divide the light without weakening in too large a degree its power. Should the system of Messrs. Molera and Cebrian prove a practical success, it may be economically used in lighting not only private residences and public institutions, but even whole cities."
Color-Blindness of Seamen.—An article on color-blindness, in a late number of the "English Mechanic," quotes some very important facts from the records of the British Board of Trade, derived from examinations of seamen applying for "mate's" or "master's" certificates, concerning their ability to distinguish colors. We select a few from the many instances of colorblindness detected by these examinations. One seaman, a candidate for a second master's certificate, described green glass as "dark red"; in another case a green card was called "yellow"; and a man who had been over eighteen years at sea was reported as quite unable to distinguish any of the colors. Another who had been more than seven years at sea described the red glass by daylight as "green," the dark green as "red," and the yellow as "red"; while by gaslight he named the light blue "green," the dark green "red," and the yellow "red." This appears to be a case of Daltonism, or incapability of perceiving the red end of the spectrum. There are several similar instances which differ only in details; but perhaps the most interesting case is that of a candidate for a second mate's certificate who had served nearly five years at sea—a case that ought to have been sent to a court of appeal. By daylight he described the red card as "green," the yellow and green glasses "red," and the red glass as "dark green." By artificial light he called the yellow and green glasses "red," and the white glass "dark green." This man obtained a certificate from the London Ophthalmic Hospital testifying that he was not color-blind, but on reëxamination he still described dark green as "red," light green as "neutral," and yellow as "red" by artificial light, while by daylight he called the green glasses "red" once and "yellow" once. This last difference may have been caused by the manner in which the question was put, and ignorance of the names of colors. In view of these facts, the query suggests itself, may not the recent dreadful accident to the steamer Champion have been due to the inability of the lookout to distinguish the lights on the other ship, which was discovered only when near enough to take in her general outline?
Apprentice-Schools in France.—This is the title of a highly suggestive paper on the subject of science teaching in the public schools, read by Professor S. P. Thompson at the last meeting of the British Association. As the subject is daily acquiring new importance in this country, we present a pretty full abstract of the paper as it appeared in "Nature." The problem to be solved, in the author's opinion, is, how to give that technical training and scientific knowledge to artisan children which their occupation demanded, without detaining them so long at their schooling as to create a distaste for manual labor. There were four solutions of the problem, all of which had been tried, and illustrations of which could be seen in Paris. They were: 1. Send the children to work in the factory or workshop at an earlier age, making it obligatory all through their apprenticeship that they should have every day a certain number of hours' schooling in a school in the workshop or attached to it; 2. Keep the children at school as long as their education was unfinished, but set up a workshop in the school, where they should pass a certain amount of time every day so as to gain at least an aptitude for manual labor; 3. Organize a school and a workshop side by side and coöordinate the hours given to study with an equal number of hours devoted to systematic manual labor; and, 4. Send the children half the day to the existing schools, and the other half to work half-time in the workshop or factory. Schools of the first type had existed in France for nearly thirty years, and at the close of 1878 there were no fewer than 237 schools of this character. So far as he was aware, there was only one school of the second type—the Ecole communale d'Apprentis, in the Rue Tournefort, Paris. The peculiarity of this school was that workshop training was being given to lads who had not yet completed a course of elementary education. Of the third type some admirable examples were to be seen in Paris. Some very interesting particulars were given of the progress of the horological school at Besançon. The fourth type or half-time school, which was English in its origin, was rarely to be found in France. Since the old apprenticeship had virtually lapsed, there was nothing to save the young artisan of the rising generation from degenerating into a mere machine, unless a new agency could be practically organized. What was claimed for the apprenticeship school was that its pupils do not possess just a bare minimum of knowledge sufficient to procure them means of subsistence in one narrow department of one restricted industry, but that they possess both manual dexterity and a fair technical knowledge which would enable them not only to earn more and to turn out better work, but also to be less at the mercy of the fluctuation of trade for the means of subsistence. Besides the new apprenticeship being better for real instruction in technical principles, it was also better for practical work in so far as it shortened the needlessly long years of the apprenticeship, and imparted at an earlier age all the manual capacity that apprenticeship in any form could impart. There were not wanting on our horizon signs of significance in the problem of the relation of science to labor. We had really skilled workmen, and no foreign workmen were their equals, but they were only units in a crowd. Take which view they would, technical education, and, above all, the technical education of the artisan classes, was a sine qua non of the future industrial prosperity of Great Britain. What steps, then, must be taken to give effect to the new apprenticeship? Two things would determine the success or failure of the school: 1. The obtaining of the right kind of teachers; and, 2. The adoption of a system of instruction based upon drawing, which was the language of the manufactures, the handicrafts, the constructive industries of all kinds. It was evident that the first step would be the foundation of a system for training competent teachers. Then there must be a central technical college, for through such an institution alone could community of thought and method of work be obtained.
Two Remarkable Epidemics.—In the spring of 1878 an epidemic of typhoid fever broke out at Zurich, Switzerland, which possesses peculiar interest. A musical festival was held in that town in May, and out of the seven hundred persons who attended it five hundred were attacked by typhoid fever, of whom one hundred died. A minute inquiry into the circumstances left but little doubt that the epidemic was due to the use of bad veal furnished by an innkeeper of the place. It may be claimed by those who attribute to general causes the power of originating specific diseases that the typhoid fever was due to a septic poison present in the veal, depending possibly on a beginning fermentation, which was not destroyed by the cooking to which it had been submitted. On the other hand, as the animal from which the meat was taken was sick, it may be asked whether it might not have been suffering from typhoid fever, although this disease has never yet been recognized among animals. It is a remarkable fact that in 1839 a similar but much less fatal epidemic occurred in a neighboring locality. After a reunion that took place under similar circumstances, four hundred and forty persons were taken sick with all the symptoms of typhoid fever. It is probable that in this case also the meat of a sick calf gave rise to the disease.
South-African Cannibals.—At the late meeting of the British Association, the French explorer Brazza read a paper on "The Native Races of the Gaboon and Ogowai." A preceding speaker, Major Serpa Pinto, had spoken of races having European characteristics inhabiting the region about the headwaters of the Zambesi. M. de Brazza was of opinion that these people had come from the north of Africa, because, under the name of Ubamba, he had found races very much resembling them to the south of the Congo. The negroes Pinto saw were probably the advance-guard of an invasion which had overrun the country to the cast of the Gaboon. Stanley spoke of a great emigration very much resembling what had taken place among the Fan cannibals. There had been much talk indulged in adverse to the cannibal races of this part of Africa. Du Chaillu, who had visited for one day only one of the Fan villages, had given a description of this race, which had been too much influenced by accounts he had received from a tribe at war with the cannibals. He had said that in their villages he had found quarters of human flesh exposed for sale; that they killed and ate their prisoners of war, and that they sold the bodies of their own dead who had died of disease to their neighbors. M. de Brazza denied the truth of such accounts. As a proof that the Fans bad kindly and generous sentiments, he told how a Fan chief had been kind to him when he was obliged to leave his people sick in the bush. He owed his life to the Fan chief, and he should always be grateful to him and his people. He wished, therefore, to do all he could to remove the prejudice against the Fans which had been excited by Du Chaillu. They were a very generous, courageous people. It was true they were cannibals—that they ate their prisoners of war; but it was with them a religious idea, for they believed that in eating the heart of a brave man the courage of the dead passed into themselves. M. de Brazza also gave an interesting sketch of the Akkas, a dwarf race he found scattered up and down among the different peoples, like what the Jews or the gypsies were in Europe. The height of the Akkas was from three to four feet.
Raising Sunken Vessel.—In the Plötzen Lake, which is not far from Berlin, and the depth of which is very considerable, reaching in some parts to twenty-eight metres, an interesting attempt has been made to raise sunken vessels. The method, which is the invention of Herr Eidner, a Vienna civil engineer, consists in applying carbonic acid in the following manner: In an empty balloon a bottle half filled with sulphuric acid, surrounded with Bullrich's salt, is fixed; the bottle is destroyed by turning a screw, and the two substances mix and produce carbonic acid, which fills the balloon. It is obvious that, when this apparatus is brought into operation in the hull of a sunken ship, the effect must be, if a sufficient number of balloons are filled, to raise the vessel. In the experiments on the Plötzen Lake, a small vessel or boat weighing several hundred-weight, was first sunk. A diver then went down with the necessary apparatus, which he set in operation in the interior of the ship. Hardly had he done so before the vessel began to rise to the surface, where it was maintained by the balloon. In a second experiment five heavy sacks filled with sand were thrown over-board, in a part of the lake which was sixteen metres deep. The diver descended, fastened all the sacks together, and, fixing the balloon apparatus to them, set it going, with the effect that the whole of the sacks were brought up to the surface.
Petroleum in Iron-making.—The successful employment of petroleum as a fuel in the manufacture of iron, has, according to the "Engineering and Mining Journal," been accomplished by a process invented by Dr. C. J. Eames, and now in practical operation at Titusville, Pennsylvania. The petroleum is vaporized by means of highly heated steam, thrown into a chamber in which the oil is caused to trickle over a series of horizontal shelves; and the mixture is then driven onward to the combustion-chamber, where it is ignited and forced into the furnaces by the air-blasts which it encounters at this point. "The evident advantages," says the "Engineering and Mining Journal," "of petroleum-fuel, are the perfect control under which the heat is held; the extremely high calorific intensity of this 'water-gas'; and the freedom of the fuel from any elements injurious to the iron. It is claimed that the work can be performed much quicker, and the quality of the product can be made much more uniform and of higher grade, than can be secured with coal-fuel."