# Popular Science Monthly/Volume 60/November 1901/Scientific Literature

Layout 4
THE METRIC SYSTEM.
To one of scientific tastes, who at the same time welcomes the recent American renaissance of the historical novel, or to one whose faith in the common sense of his countrymen may waiver on considering their apathy towards the metric system, a recent work by M. Bigourdan will have great fascination. Nor are these words carelessly chosen, for a more fascinating work on any phase of the history of science has not appeared in recent years. It is true that the topic seems trite enough. All the world knows the story, or thinks it does; the French revolution, the general upheaval, the different systems proposed, Méchain's mistake in the longitude of Barcelona, the consequent error in the meter, the final adoption of the system by a large majority of the civilized countries, all this is familiar. But one has only to read a dozen pages of M. Bigourdan's work to find himself in the midst of a wealth of interesting history of which he probably never even heard.
The fact is, it needed some one connected with the Paris Observatory to write such a work, and even he could not have done it until of late. For although the observatory has long had in its possession the original documents deposited there by virtue of a decree of the year 12, it is only recently that it received the valuable manuscripts relating to the early history of the system, which were given by Mme. Laugier, who had received them from her father, M. Mathieu, who in turn had them from a no less important actor in the drama than M. Delambre himself.
It is impossible to give in a few words any worthy résumé of the work, or adequately to speak of its style. It opens with a chapter on the precursors of the reform, going back even to the system under Charlemagne, to the effects of feudalism and to the efforts of such early leaders as Mouton, Huyghens and Wren. This is followed by a statement of the action of the Assembly on Talleyrand's proposition, the history of the provisional meter, the work of the temporary commission, the efforts at nomenclature and so on through the establishing of the system on a scientific foundation. Then come the long story of its adoption by France, ending with the law of July 4, 1837; the longer story of its struggles for recognition in other countries, and the later history of the International Bureau and its remarkable metrological labors at St. Cloud.
Still less is it possible to give, in the limited space at command, any idea of the thrilling historic action so unassumingly stated in the documents at M. Bigourdan's command. The difficulties of men like Delambre and Méchain, unable to make surveys without being suspected of signaling to the enemy, arrested as spies because they wished to visit their triangulation stations, imprisoned, insulted, limited in the bare necessities of life, the only wonder is that other errors than that of Méchain did not find frequent place in the work. 'I am an academician,' said Delambre to a sansculotte who ​examined his passports. 'There isn't any Cadémie, no Cadémie at all,' blurts out the surly guard; 'all the world's equal. You come along with us!'
To the American scientist, educator or promoter of foreign trade, however, the chief interest in the work lies in the story it tells of the adoption of the system by most of the non-English speaking countries of the world. The common objections of those who have given the subject little thought, objections to nomenclature, to the magnitude of the units, to the difficulty of educating the people, to the error in the meter, objections which have been so thoroughly considered in the century past and in so many countries, and which have proved of so little consequence—these are considered fully and judiciously. It will be unfortunate if some of the societies interested in the progress of the system do not arrange for translating the entire work, both for the enlightenment of those who have given the subject little attention and for the help of those who believe that America can no longer afford to stand out against a system which the great majority of civilized nations are using.
BOOKS ON NATURE STUDY.
'The Sea-beach at Ebb-tide,' by Augusta Foote Arnold (The Century Co. ), meets a well-defined need for popular accounts of the natural history of the seaside. It describes the animal and plant life found on the beach and rocks between tide marks and washed up after storms. There are chapters on the distribution of animals and plants, on methods of collecting and preservation, on classification and on various peculiarities of certain groups. Then follows an account of the marine algae and marine invertebrates, systematically arranged with the formality of a manual. This portion of the book is abundantly illustrated with photographic reproductions. Some of these are very good. but many are not as clear as could be wished and do not compare favorably with the beautiful book work exhibited in some of the recent popular accounts of flowering plants. That the book is far from being strictly accurate becomes apparent to any one who critically examines the treatment of groups with which he is familiar. Nevertheless the conspicuous forms are in the main sufficiently described and, what is more important, so figured that the tyro will have little difficulty in identifying specimens at hand. There is sure to be much confusion, however, of the more minute types such as the hydroids with the delicate filamentous seaweeds that should be studied with the compound microscope.
The author's attitude towards classification seems strained. The account of every large group is prefaced by a table of the families, genera and species to be considered. These synopses remind one of the outlines found in dictionaries and are very far from the spirit of classification that now dominates natural history. Such arrangements have but small and passing value in the constantly shifting scenes of systematic zoology and botany. Emphasis laid upon classification throws into the background the wealth of interest in the life and habits of organisms which we term their natural history. But a more important criticism is the loose and inaccurate conception of the significance and use of nomenclature. When the author says that specific names are 'occasionally the names of botanists who first described the plants' (p. 29), she shows much ignorance of the methods of systematists. It seems that the spirit of the present-day natural history is rather against collecting, that the best thought is directed to the out-of-doors study of particular groups in some detail rather than to the recognition of a very large number of forms, to the study of their home life with camera and sketch book rather than to ​the most interesting popular books on natural history in recent years have exhibited a very intimate knowledge of the forms considered. There is a charm in familiar friendship that is far more satisfactory than casual acquaintance, and it is a matter of small importance what the forms are—whether birds or bees or some group of plants.
One can hardly ask for a better piece of book work than 'Flowers and Ferns in their Haunts' by Mabel Osgood Wright (Macmillan). The charm lies in the beautiful photographic reproductions. These exhibit the details of flowers or ferns in the foreground against rock and in other picturesque situations with a sharpness that is very remarkable and in most delicate contrast to the soft backgrounds. With this detail is a choice of subjects in their surroundings that shows great feeling for the appropriate and artistic. The text is a running account of walks and rides in woods and over hill and dale in varying seasons of the year. The descriptions, chiefly of flower societies, are quite free from technicalities. The point of view is always imaginative and human rather than scientific. The book can scarcely be said to be botanical, except that flowers form the subject of a pleasing account of nature in her varying moods always treated figuratively and with much personification. Two human characters beside the author are carried through the book, one a quaint and interesting old man, the other a conventionally educated young woman, whose presence except as a foil seems somewhat out of place in these pages.