Popular Science Monthly/Volume 48/February 1896/Fragments of Science
Fragments of Science.
The Anniversary Meeting of the Royal Society.—The anniversary meeting of the Royal Society was held in its apartments at Burlington House, London, on St. Andrew's Day, Saturday, November 30, 1895. After the delivery of the presidential address by Lord Kelvin, the medals were presented as follows; The Copley medal to Prof. Karl Weierstrass, for Mem. R. S. (received on his behalf by the Foreign Secretary), for his investigations in pure mathematics; a Royal medal to Prof. James Alford Ewing, for his investigations on magnetic induction in iron and other metals; a Royal medal to Dr. John Murray, for his services to biological science and oceanography, in connection with the Challenger reports, and for his original contributions to the same; and the Davy medal to Prof. William Ramsay, for his share in the discovery of argon, and for his discoveries regarding gaseous constituents of terrestrial minerals. The officers elected for the ensuing year are as follows: President, Sir Joseph Lister, Bart.; Treasurer, Sir John Evans; Secretaries, Prof. Michael Foster and Lord Rayleigh; Foreign Secretary, Mr. Edward Frankland. Lord Kelvin closed his address with the following remarks: "I thank you all, my colleagues of the Royal Society, for electing me five times to be your president, for forgiving me all my shortcomings, and for the inestimable benefit which you have conferred on me by giving me your friendship." In the evening the anniversary dinner was held at the Hôtel Métropole, when the newly elected president, Sir Joseph Lister, occupied the chair. The retiring president, in his anniversary address, and several of the speakers at the dinner, dwelt at some length on the great loss which Bcience and humanity had sustained through the deaths of Huxley and Pasteur.
Pastenr's Snccessor. We take the following note from the Practitioner: M. Emile Duclaux, who has just been appointed Director of the Pasteur Institute, in succession to M. Pasteur, was his former chief's oldest collaborator, and had held the post of subdirector under him since the foundation of the institute. He wasbornat Aurillacin 1840, and was Pasteur's assistant in the Ecole Normale from 1862 to 1865. After teaching for a time in the Tours Lycee in 1865-66, he was appointed Professor of Chemistry at Clermont in 1866, and afterward of Physics in the Lyons Faculty of Sciences in 1873. In 1878 he came back to Paris as Professor of Physics and Meteorology in the Institute Agronomique, and iu 1888 he was appointed Professor of Biological Chemistry in the Faculty of Science. M. Duclaux took the degree of Doctor of Science in 1862; but, like Pasteur himself, he is not a member of the medical profession, although in 1894 he was elected a member of the Academy of Medicine. He is the editor of the Aunales de I'Institut Pasteur. Apart from his contributions to chemistry, silkworm culture, the phylloxera, etc., ha has done valuable work on ferments and their relation to disease, digestion, milk, and microbiology.
The Feeding of Infants. The time when a bottle-fed baby was a rare thing is within the memory of all of the older physicians; but now it is the exception rather than the rule for a mother to suckle her child. Many a mother who really wants to nurse her baby, but because of her small supply of milk is prevented, might, by a little judicious advice as to diet and proper habits, be rendered perfectly competent. Instead of this, that convenient bottle is adopted, which is thus graphically described by Dr. Mary A. Willard: "' When the poor, pinched, blue, weazened little creatures were brought to me in the dispensary in New York, where they used to come by the dozen, I would call for their nursing-bottles, take a whiff of their sour, putrid contents, swarming with bacteria, pull off the rubber nipple and the ivory guard, rip up the long tube with my penknife, and scrape ofP the green, poisonous matter, tyrotoxicon, and spread it out on my palm before the astonished mother." Combine with such a state of affairs in the bottle some one of the dry milk foods, or a diluted condensed milk, and the babies' chances are pretty slim. The dry milk powders, including malted milk, are, from their nature, deficient in fats and contain a large excess of sugar, which is harmful because of the readiness with which it undergoes fermentation. As for the condensed milks, during a recent examination of the milk supply of London, seventeen brands were examined; fourteen of these were found to have been prepared entirely from skimmed milk, and showed an average of only 0-'72 per cent of fat. Genuine full-cream brands of condensed milk contain from ten to twelve per cent of fat. Considering the far-reaching and deplorable effects which reliance upon such foods must lead to, it is of the utmost importance that physicians and parents should understand the dangers of prepared-milk feeding.
Examinations. From a recent address delivered by Jonathan Hutchinson, and published in the Lancet, we quote the following very pertinent passages: " Examinations should be made as little distasteful as possible. The candidate ought to feel throughout his studies that in presenting himself to an examiner he does that which is equivalent to placing himself on a weighing machine, and that the verdict recorded will be in exact relation to his deserts. . . . The personal element, that of the examiner, should be eliminated as far as possible. To this end vivavoce examinations should, as far as practicable, be avoided. I have heard a selfconfident examiner allege that he could tell better what was in a man in five minutes' conversation than by reading any number of his written papers, and I did not doubt that he thought so. This judgment of men, as it were, by personal inspection is often most fallacious, and should be permitted only with the utmost circumspection. It by no means follows that the disuse of the viva voce would throw us back wholly on set verbal questions. There remains the extensive field of objective examination. . . . This kind of examination it is which conduces most of all to sound matter-of-fact objective teaching. It is perhaps the most important of all modes, and is one which in the future is destined to receive more and more attention. We come next to the consideration of papers and of paper-setting. It is the fasliion to hold that any one who knows his subject can examine in it, but in truth it is not so, and the art of examining is one which, like other arts, needs to be learned. It is impossible to deny that many examination papers are ill expressed, and some wholly unsuitable. It is no legitimate part of an examination to take the candidate by surprise, or confound him with the .unexpected. Nor should half of the time allowed be taken up in the effort to understand what the terms of the question are intended to mean. . . . Modern education, in its zeal to avoid the charge of being superficial, incurs, as it seems to me, that of being merely fragmentary. It aims at thoroughness, but is obliged at once to admit that it can attain it only in certain subjects which, compared with the sum of human knowledge, are but few and small. . . . Excepting a very few of us, we are all mere smatterers as regards almost all that we think we know. It is not possible to be otherwise, excepting at the cost of being wholly ignorant in many directions; and as regards fitness for the affairs of hfe, better by far a general acquaintance with all that is around us, though it be not very deep, than slices of profound knowledge placed sandwichwise between thick layers of utter ignorance."
Hygiene of OysterSt Prof. Herdman and Prof. Bryce have found, from experiments on the effect upon oysters of various conditions with especial reference to the typhoid germ that beneficial results are derived from aeration, and therefore that it is salutary to lay the moUusks down where there is a good change of water. Of foods given to oysters, sugar caused them to lose weight and die; oatmeal and flour had like effects. Stagnation was deleterious, causing the accumulation of excretory products, and encouraging the growth of micro-organisms and the formation of scums on the surface of the water; yet the oysters were tolerant of sewage, and could, up to a certain point, render water clear that was contaminated with it, and they -could live a long time in water rendered opaque by fecal matter. The fecal matter from typhoid subjects was more inimical than that obtained from healthy ones. The oysters were found very prone to infection by micro-organisms, but the typhoid bacillus will not flourish in clean sea-water; and the experiments seem to show that this organism decreases in numbers in passing through the alimentary canal of the oyster. It seems possible, therefore, that by methods similar to those employed in the clearing basins of the French ostreoculturists oj'Sters previously contaminated with sewage can be freed from pathogenic organisms or their products without being spoiled for the market.
Engineering as an Exact Science. So
far as it is based on mathematics, said Mr. L. F. Vernon Harcourt in the British Association, engineering is an exact science, and the strains due to given loads on a structure can be accurately determined; but the strength of the materials employed has to be ascertained before any structure can be properly designed. Accordingly, the resistance of materials to tension, compression, and flexure has to be tested and their limit of elasticity and breaking weight to be determined. Numberless experiments have been made on the flow of water in open channels, over weirs, through orifices, and along pipes, and the influences of the nature of the bed, the slope, depth, and size of the channel have been investigated. Electrical engineering is especially adapted for experimental investigation, but every branch of engineering science is more or less capable of being advanced in the same way; and when it is borne in mind that the force of waves, the ebb and flow of tides in rivers, the influence of training works in estuaries, and the motion of ships at sea have been subjected to experimental research, it appears impossible to assign a limit to the range of experiments as a means of extending engineering knowledge. The correct calculations of strains, the exact strength of materials, and a strict appreciation of the physical laws afi"ecting designs are of the utmost importance, and the failure of many bridges might be explained by a neglect of these considerations. Occasionally failui-es of works might be attributed to exceptional causes or peculiarly unfavorable conditions, but in most cases they are the result of errors or deficiencies in design which might have been avoided by a more correct appreciation of the physical conditions involved.
Eleetrical Effects of Spray. A correspondent, writing to us concerning the effect of various atmospheric conditions on health and bodily vigor, cites his own experience in a fire brigade as having led him to believe that deficiency of ozone and other unfavorable conditions and the effect of atmospheric impurities may be alleviated by inhalation through a spray of cold water. A method of ventilation of railroad cars which was very comfortable to passengers riding in cars so treated, but has been disused, depended upon the application of this principle. Its value is further confirmed by what Prince Kropotkin has said in one of his recent articles on current science concerning the theory of the development of electricity by spattering water. A few years ago Herr Lenard undertook a series of observations in Switzerland on the electrical effect of waterfalls. It appeared that even small cataracts, only a few feet high, send into the air considerable charges of electricity, provided they bring down a large amount of rapidly dashing water. The smallest jets of water that drip on the rock sides, and even roaring streamlets, have the same effect. He suggested that the chief cause of electrification is the tearing asunder of the drops of water as they fall on the wet surfaces at the bottom of the waterfall. The experiments on which these views are founded accord
with the demonstration by Lord Kelvin and Messrs. Maclean and Goto that air, even absolutely dust free, can be electrified by a jet of water. This source of electrification is further shown to be by no means insignificant, and the amount of electricity sent into the air in this way is immense. The importance of these facts in the economy of Nature, says Prince Kropotkin, is self-evident. "The supply of electricity in the air is continually renewed. The waterfalls in the valleys, the splashing of the waves on the shores of lakes and rivers, and the splash of drops of rain on the ground send masses of negative electricity into the air; even the watering of our streets and of our plants in the orchards has the same effect on a limited scale. On the other side, the waves of the sea, as they break against the rocks and fall back in millions of di-oplets upon the beach, supply the air with masses of positive electricity the amount of which rapidly increases after each storm. And when we stand on a sea beach we not only inhale pure ozonified or iodized air; we are, so to say, surrounded by an electrified atmosphere, which, as already remarked by Humboldt and often confirmed since, must have a stimulating eilect upon our nei'vous activity as well as upon the circulation of sap in plants."
The Sciences Auxiliary to Engineering.
Among the branches of science necessary for the engineer, Mr. L. F. Vernon Harcourt, in his address at the British Association meeting, named mathematics and physics as of the highest importance, and as those upon which the profession mainly depends. Other sciences of considerable though comparatively minor importance are those of chemistry, meteorology, and geology. All branches of applied mathematics have to be used by engineers, or, as in the case of several general principles and tidal calculations, by mathematicians, for their benefit; but graphic statics will probably gradually supersede analytical methods for the calculation of stresses, as more rapid and less liable to errors, which are also more easily detected in graphic diagrams Pure mathematics, in its higher branches, appears to have a less direct connection with engineering; but applied mathematics is so largely dependent upon pure mathematics that this, including the calculus and differential equations, can not be safely neglected by the engineer though some of the more abstruse portions of the subject might be dispensed with. Physics is of great importance, for there are few problems in engineering in which no part is borne by physical considerations. The surveyor avails himself of physics when heights are measured by the barometer, or by the temperature at which water boils. Evaporation, condensation, and latent heat bear upon the efficiency of steam engines, and the expansive force of gases, the retention of the heat developed, and the diminution of friction on the economical working of heat engines. Considerations of temperature limit the height to which railways can be carried without danger of blocking by snow, and the depth at which tunnels can be driven. Compressed air is largely used by engineers. Electric engineering, too, is intimately connected with physics. Chemistry is of importance in the manufacture of iron, steel, and other metals, and the formation of alloys, and in its relation to explosives. A knowledge of geology is indispensable in directing a search for coal, iron ore, and the metals, and in the execution of all works going below the surface. Meteorology is useful to the engineer in that it enables him to know the force of the wind and the direction, duration, and periods of occurrence of severe gales very important matters in the construction of bridges and harbor works,
A Valley of White Limestone. A remarkable formation is described by Mr. Theodore Bent as observed by him while exploring the frankincense country of Arabia, near the presumed site of the Abyssapolis of Ptolemy. The valley leading down to the Red Sea has been filled in the course of ages by a calcareous deposit, which is collected on either side of an isolated hill in the middle of the hollow, about one thousand feet in height. This deposit has taken the form of a straight and precipitous wall five hundred and fifty feet high and three quarters of a mile long on the eastern side of the bill, and about a quarter of a mile long and three hundred feet high on the western side. Over these walls feathery waterfalls precipitate themselves, adding perpetually to
the chalky accretions of which the cliffs are constructed. The general appearance of the walls is white and whitish- gray, with long, white stalactites hanging down in tumbled confusion. They ai-e streaked here and there, where the water perpetually falls, with patches of green. Beneath plateaus twenty feet high enormous ricinuses, daturas, and other plants flourish; and the Bedouins have utilized the stream before it has lost itself in the rocky channel to make small gardens. The rocky channel below is also very curious, presenting a flat surface about fifty yards across of white calcareous rocks, while just below the wall where the water comes down is an enormous amount of white calcareous deposit, soft and spongy to walk upon. Mr. Bent pronounces this one of the most stupendous natural phenomena he has ever seen, characterizes the valley as "a stupendous abyss," and compares the whole with the pink and white terraces of New Zealand and the calcareous deposits of Yellowstone Park.
Geology and Paleontology at Union University. The department of Geology and Paleontology of Union University offers the ordinary course of the college and special courses for such students as are interested in the science from a philosophical or professional point of view. The courses include mineralogy and lithology, general geology (with excursions), economic geology, in which are considered in the second half the occurrence and distribution of the mineral deposits and building stones of the United States; systematic and structural geology and paleontology, with especial consideration of the formations occurring in New York and adjacent States and their characteristic fossils; field and laboratory study of the geological formations readily accessible from Schenectady; the methods of preparing geological maps and reports; and advanced field work and independent research, in which the student selects some region for original work to which he can devote considerable time, and conducts his investigation in a professional manner. He is expected in this to demonstrate his ability to conduct original work, and to prepare a report containing a summary of the previous knowledge of the geology of the region, with a detailed account of his investigations—the whole to constitute a contribution to knowledge. In studying paleontology the student receives careful training in systematic classification. Candidates for honors must prepare theses of sufficient merit to warrant the publication of at least an abstract in some scientific journal. As aids, students have access to the library and museum of Union College, and to the State Library and Museum at Albany.