March 26, 1903 



NA TURE 



495 



in a steel flask. The last apparatus described is a hydrogen 

 liquefier which differs from that of Dr. Travers chiefly by 

 the insertion of a second regenerator coil, which serves 

 almost wholly to equalise the temperatures of the arriving 

 and the issuing hydrogen, and by the absence of a low 

 pressure chamber for liquid air, this refrigerant being used 

 boiling under atmospheric pressure. The preliminary ex- 

 periments carried out with this apparatus are said to have 

 led to satisfactory results. 



A series of articles by Prof. Duhem, of Bordeaux, on the 

 evolution of mechanics, is an important feature of the 

 current numbers of the Revue ginerale des Sciences. It 

 commences in the issue of January 30 with a historical 

 account of the development of dynamics, starting with the 

 Greek notions of matter, and tracing the successive theories 

 of Descartes, Leibnitz, Boscovich, Newton and Laplace. 

 In the second part, Prof. Duhem deals with the principle 

 of virtual velocities and the statics of Lagrange, d'Alem- 

 bert's principle, the Lagrangian equations of motion, the 

 theories of Poisson on elasticity, hydrodynamics and 

 capillarity, and theories of elasticity generally. The third 

 paper is devoted to Prof. Duhem 's favourite subjects of 

 study, heat and electricity, especially the former. The 

 kinetic theory of gases is traced from its first introduction 

 in the " Hydrodynamica " of Daniel Bernouilli down to 

 the latest works of Boltzmann. In the section devoted to 

 thermodynamics, we have an account of the discoveries of 

 the first and second laws, Helmholtz's theory of monocyclic 

 systems, and a detailed examination of Gibbs's recent work 

 on statistical mechanics. The dynamical theories of elec- 

 tricity are considered, with especial reference to Clerk 

 Maxwell. Finally, under " Impossibility of Perpetual 

 Motion," we have a critical exposition of the dynamics of 

 irreversible phenomena and Clausius's principle of entropy. 

 Further papers are promised dealing with the revival of 

 atomism, the foundations of thermodynamics and similar 

 subjects. On all these branches of theoretical physics Prof. 

 Duhem speaks with authority, and his papers form a useful 

 summary of the development of modern views of the 

 dynamical properties of matter. 



The Naturalist for March contains an account of the work 

 of the Yorkshire Boulder Committee for 1901-2. 



In Naturwissenschaftlicke Wochenschrift of March 8 Herr 

 L. Plate concludes his account of Weismann's theory of 

 development. 



We have received the Transactions of the City of London 

 Entomological and Natural History Society for 1902, which 

 contain the president's address and a number of papers. 



Dr. O. Zacharias, in Biol. Centralblatt of March 1, gives 

 an account of the plankton of the Thames, based on the 

 investigations recently undertaken by Dr. F. E. Fritsch, 

 of the Jodrell Laboratory at Kew. 



The Anales of the National Museum of Buenos Aires (vol. 

 i. part ii. of the third series) contains three papers by Dr. 

 Ameghino. In the first of these, the author describes a 

 number of mammalian remains — mostly fragmentary — 

 from the well-known deposits of Tarija, in Bolivia, naming 

 several species as new. The age of the Patagonian 

 mammaliferous deposits forms the subject of the second 

 communication; while in the third the primitive type of 

 mammalian molar teeth is discussed. 



An interesting account of the mode of life of the giant 

 land tortoises of the Galapagos Islands, and the present con- 

 dition of the different species, is given by Mr. E. Heller in 



NO. I743, V0L - 67] 



vol. v. of the Proceedings of the Washington Academy. From 

 several of the islands of the group, the tortoises have disap- 

 peared ; in Indefatigable Island, the extermination appears 

 to have been quite recent, some Ecuadorians having told 

 the author that not many years ago they saw a huge tor- 

 toise near the central crater. The land and sea iguanas 

 of the Galapagos, and their habits, also come in for a share 

 of attention, the author describing the land iguana of 

 Barrington Island as a new species, under the name of 

 Conolophus pallidiis. 



A memoir on the geology of the country around Salisbury, 

 by Mr. Clement Reid, has just been issued by the Geo- 

 logical Survey. It is accompanied by a capital colour- 

 printed map, and both will no doubt be welcomed by the 

 members of the Geologists' Association who make Salisbury 

 their head-quarters for an excursion at Easter. The famous 

 vale of Wardour, with its Portland and Purbeck strata at 

 Tisbury and Chilmark, the Greensand and Chalk of the 

 bordering heights, the Chalk of Salisbury Plain, and the 

 Tertiary and Pleistocene deposits are duly described. It is 

 interesting, too, to find approval of the Eolithic implements 

 which Dr. Blackmore has so assiduously gathered together 

 from the pits of Alderbury. 



M. Charles Rabot, secretary of the French Commission 

 on Glaciers, is the author of a pamphlet entitled " Essai de 

 Chronologie des Variations Glaciaires " (extract from 

 Bulletin de Geographie Historique et Descriptive, No. 2, 

 1902). In this work the author discusses the observations 

 which he has collected from numerous places in different 

 parts of the world, and comes to some interesting con- 

 clusions, which he summarises at the end. To state in a 

 few words the results obtained, he points out that the same 

 kind of glacial variation does not occur simultaneously in 

 the regions he investigated ; thus the last positive variation 

 extended over a century and a half, the beginning of the 

 primary increase occurring in Norway in 1700, and ending 

 in the Alps in 1855-1860. A complete primary oscillation, i.e. 

 an increase and decrease, appears to have a duration of one 

 or two centuries. For Norway, for instance, the last 

 primary increase began in 1700, and the decrease has not 

 yet terminated ; many other examples are given. There 

 seems further to be a plurisecular period covering, in the 

 case of the Alps, about three centuries. 



The Cresham Publishing Company has published, in 

 drawing-book form, two capital models to show graphically 

 the structure of the bee. One model is of the queen bee, the 

 other of the drone. By the familiar device of overlapping 

 sheets, suitably shaped and coloured, the external anatomy, 

 the organs of respiration, digestion and reproduction, as 

 well as the nervous system, can be followed by successively 

 raising the sheets, which, when folded down, make realistic 

 models of the two bees. 



The fourth instalment has been issued of the report on 

 the physical and chemical soil survey of Dorsetshire, begun 

 in 1S98, and being conducted by the Department of Agri- 

 culture of the Reading University College. In an intro- 

 ductory note Prof. Percival, the director of the Agricultural 

 Department, says it is hoped that during the present season 

 an examination will take place of the flora and plant 

 associations, more especially of the pastures and meadows, 

 met with upon the different formations and drift areas of 

 Dorsetshire. A thorough botanical or cecological survey 

 taken in conjunction with geological and analytical data 

 will be of great value, and it is proposed, if possible, to 

 secure the assistance of Dorset field botanists. 



