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572 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 fashion 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 life, 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 Oysters—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 aëration, and therefore that it is salutary to lay the mollusks 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 oysters previously contaminated with sewage can be freed from pathogenic organisms or their products without being spoiled for the market.

Bibliography of Zoology.—The International Bibliographical Bureau for Zoölogy, 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 Bulletin, 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 catalogue of all zoological literature published after 1895; besides which the Zoologische Jahresbericht will be federated with the undertaking, 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, correspondents, 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 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