Popular Science Monthly/Volume 48/February 1896/Fragments of Science

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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 FRAGMENTS OF SCIENCE.


��Bcience and humanity had sustained through the deaths of Huxley and Pasteur.

Pastenr's Snccessor. We take the fol- lowing note from the Practitioner: M. Emile Duclaux, who has just been appointed Di- rector of the Pasteur Institute, in succession to M. Pasteur, was his former chief's oldest collaborator, and had held the post of sub- director 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 Cler- mont 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 con- tributions to chemistry, silkworm culture, the phylloxera, etc., ha has done valuable work on ferments and their relation to dis- ease, 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. Wil- lard : "' When the poor, pinched, blue, weaz- ened 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, tyro-

��toxicon, 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 malt- ed 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 ex- amination 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 pub- lished in the Lancet, we quote the follow- ing very pertinent passages : " Examinations should be made as little distasteful as possi- ble. 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 re- lation to his deserts. . . . The personal ele- ment, that of the examiner, should be elimi- nated as far as possible. To this end viva- voce examinations should, as far as prac- ticable, be avoided. I have heard a self- confident 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,

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��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 legiti- mate 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 under- stand what the terms of the question are in- tended to mean. . . . Modern education, in its zeal to avoid the charge of being super- ficial, incurs, as it seems to me, that of being merely fragmentary. It aims at thorough- ness, 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 af- fairs of hfe, better by far a general acquaint- ance with all that is around us, though it be not very deep, than slices of profound knowl- edge placed sandwichwise between thick lay- ers of utter ignorance."

Hygiene of OysterSt Prof. Herdman and Prof. Bryce have found, from experiments on the effect upon oysters of various condi- tions with especial reference to the typhoid germ that beneficial results are derived from aeration, and therefore that it is salu- tary 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 ac- cumulation of excretory products, and encour- aging the growth of micro-organisms and the formation of scums on the surface of the water ; yet the oysters were tolerant of sew- age, 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 in-

��imical than that obtained from healthy ones. The oysters were found very prone to infec- tion 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 mar- ket.

Bibliography of Zoology. The Interna- tional Bibliographical Bureau for Zoology, the organization of which was begun about three years ago, will be located, Mr. H. H. Field announces, at Zurich, Switzerland. It will publish a fortnightly bibliographical Bul- letin, with an edition printed on thin paper and on only one side of the sheet, so that it may be cut up ; and a complete card cata- logue of all zoological literature published after 1895; besides which the Zoologische Jahresbericht will be federated with the un- dertaking, so as to afford an annual list of titles, arranged alphabetically, by authors. The bureau will be aided in various parts of the world by national committees, corre- spondents, and sub-bureaus.

Engineering as an Exact Science. So

far as it is based on mathematics, said Mr. L. F. Vernon Harcourt in the British Asso- ciation, 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 resist- ance of materials to tension, compression, and flexure has to be tested and their limit of elasticity and breaking weight to be de- termined. 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 experi- mental 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 ap- pears impossible to assign a limit to the range of experiments as a means of extend- ing 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 er- rors or deficiencies in design which might have been avoided by a more correct appre- ciation of the physical conditions involved.

Eleetrical Effects of Spray. A corre- spondent, 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 unfavor- able 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, de- pended upon the application of this princi- ple. Its value is further confirmed by what Prince Kropotkin has said in one of his re- cent 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 water- falls. It appeared that even small cataracts, only a few feet high, send into the air con- siderable 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 roar- ing streamlets, have the same effect. He suggested that the chief cause of electrifica- tion 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 ab- solutely dust free, can be electrified by a jet of water. This source of electrification is further shown to be by no means insignifi- cant, and the amount of electricity sent into the air in this way is immense. The impor- tance of these facts in the economy of Na- ture, says Prince Kropotkin, is self-evident. " The supply of electricity in the air is con- tinually renewed. The waterfalls in the val- leys, 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 nega- tive electricity into the air ; even the watering of our streets and of our plants in the or- chards 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 elec- tricity 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 al- ready remarked by Humboldt and often con- firmed 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 Har- court, in his address at the British Associa- tion meeting, named mathematics and phys- ics as of the highest importance, and as those upon which the profession mainly de- pends. Other sciences of considerable though comparatively minor importance are those of chemistry, meteorology, and geol- ogy. 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

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��that this, including the calculus and differ- ential 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 impor- tance, for there are few problems in engi- neering in which no part is borne by phys- ical considerations. The surveyor avails him- self of physics when heights are measured by the barometer, or by the temperature at which water boils. Evaporation, condensa- tion, and latent heat bear upon the efficiency of steam engines, and the expansive force of gases, the retention of the heat devel- oped, and the diminution of friction on the economical working of heat engines. Con- siderations 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 execu- tion 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 re- markable formation is described by Mr. Theodore Bent as observed by him while ex- ploring 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 col- lected 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 quar- ters 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 pre- cipitate 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, da- turas, 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 phe- nomena he has ever seen, characterizes the valley as " a stupendous abyss," and com- pares the whole with the pink and white ter- races 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 spe- cial courses for such students as are inter- ested in the science from a philosophical or professional point of view. The courses in- clude mineralogy and lithology, general geol- ogy (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 considera- tion of the formations occurring in New York and adjacent States and their char- acteristic fossils ; field and laboratory study of the geological formations readily acces- sible from Schenectady ; the methods of preparing geological maps and reports ; and advanced field work and independent re- search, in which the student selects some region for original work to which he can de- vote considerable time, and conducts his in- vestigation 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.

Antiquity of the Quichuas.—Dr. George A. Dorsey expresses his belief, in a paper on The Character and Antiquity of Peruvian Civilization, that the Quichuas came into Peru from the north, and that the time of their arrival must have been a great while ago, "perhaps several thousand years. The fact that they had thoroughly domesticated the llama as well as other smaller animals is in itself proof of great antiquity. The same holds true in regard to the high state of cultivation in which we find the cotton plant, several varieties of maize, and other cereals and food products. In the province of Huarochiri, Avila states that the origin of the great acequias and irrigating canals was only accounted for by a myth, their construction dating back to so remote a period that they were no longer ascribed to human agency."