Notices respecting Sew Books. 395 
the subject; given at the end of the book, which extends over 
nearly 20 pages and contains hundreds of references. A thorough 
knowledge of the history of a subject such as that aealt with in 
the present volume is essential to all would-be discoverers and 
inventors, as it prevents waste of time and — what is perhaps more 
trying — bitter disappointment at finding that an apparently new- 
invention was well known to an older generation. We can give 
no higher praise to the volume than by saying that it is fully 
worthy of its author's reputation, and that the arduous task which 
he has attempted has been accomplished with all the thoroughness 
which might have been expected of him. 
Annua ire pour VAn 1908. Public par le Bureau des Longitudes. 
Avec des Notices scientificpies. Paris : Gauthier-Yillars. 
This year's issue of the Annuaire contains various physical and 
chemical tables, and the following special articles : — La distance 
des astres et en partiadier des etoiles fixes, by M. G. Bigourdan ; 
and L'Ecole d' Astronomic pratique de TObseruatoire de Jlontsouris. 
by M. E. Guyon. 
The Science Year Bool- and Diary for 19<>N Edited by Major 
B. E. S. Badex-Powell. 
The fourth issue of this year-book differs but little from its 
predecessor. The diary part of the book is as before of paper of 
excellent quality. The ;i Biographies " section is still very 
imperfect. We note that Professor Eutherford's address is given 
as " McGill University, Montreal.'* 
Lecons sur la. Yiscosite des Liquides et des Gaz. Par Mahcee 
Beillouix, Professeur au College de Prance. Seconde Partie. 
Yiscosite des Gaz. Caracteres Generaux des Theories 
Moleculaires. Paris : Gauthier-Yillars. 1907. Pp. 142. 
The author commences this concluding volume of a treatise on 
viscosity by a description of the earlier researches on the viscositv 
of gases, in which the pendulum and oscillating disk methods were 
employed. The experiments of O. E. Meyer, Bessel, and Girault 
are dealt with and criticised. The next chapter is devoted to an 
account of the researches of Maxwell, Kundt and Warburg ; the 
various forms of apparatus employed by these physicists are 
illustrated and described very fully. The flow of gas through a 
cvlindrical tube is next dealt with, and a:i excellent resume is 
given of the work of Graham, Meyer, and Warburg. Absolute 
determinations, the viscosity of gases at high temperatures, and 
the behaviour of vapours are then considered, while various 
comparatively recent determinations are described in the last 
chapter of the first Section of this volume. 
The remaining Section is devoted to molecular theories. After 
a brief historical survey of the subject, the author deals first with 
the kinetic theorv of gases, and then sketches the outlines of the 
