BOOK REVIEWS. 



157 



facts in this direction is already available, though a great deal remains 

 to be done. 



The author recognizes the dangers of placing too great reliance upon 

 the composition of the soil as revealed by chemical analysis as a direct 

 guide to manuring, as well as the folly of relying upon the analysis 

 of the plant; and the reader will find plans by which he may gain 

 information regarding the mianurial requirements of the plant by means 

 of trial plots. 



Altogether the author has produced an excellent book, which 

 farmers, fruit-growers and market gardeners who have some knowledge 

 of elementary chemistry will find valuable. 



"The Young People's Microscope Book." By Eev. S. N. 

 Sedgwick, M.A. 8vo., 300 pp. (Culley, London, 1910.) 3s. 6^^. net. 



This book is intended to give young people plain directions as to 

 the use of a cheap compound microscope, with methods of constructing 

 apparatus at a merely nominal cost, and to direct their attention towards 

 the most profitable places in which to search for interesting objects. 

 The author is an enthusiast upon his subject, and the youthful enquirer 

 would find in him a genial and safe guide to the mysteries of microscopy 

 so far as a beginner with, a small instrument and plenty of inquisitive- 

 ness may hope to know them. 



"Manual of Physical Geography." By F. V. Emerson, Ph.P). 

 8vo., xvii. + 291 pp. (Macmillan, New York, 1909.) 6.s. net. 



This is a school-book of physical geography, consisting mainly of 

 a variety of exercises, and applying for the most part to conditions 

 obtaining in the United States. The teacher desirous of furthering 

 Nature-study will find herein some stimulating suggestions. 



"Common Weeds of the Farm and Garden." By H. 0. Long, 

 B.Sc, and J. Percival, M.A., F.L.S. 8vo., xvih. + 451 pp. (Smith, 

 Elder, London, 1910.) 65. net. 



There are many books dealing with fungus and animal pests of the 

 farm and garden, but we have waited long for one On weeds, and now 

 it has come we can have nothing but praise for it. Weeds are not an 

 altogether unmixed curse to the gardener, for sometimes he is induced 

 to hoe between crops to keep them down, and the crops naturally benefit 

 greatly; and weeds are often useful in other ways, but some are master- 

 ful and well adapted to hold their own against most of the garden's 

 crops. 



In the present work, which is well and copiously illustrated and 

 well printed on good paper, one may learn not only how to identify 

 the weeds commonly met with, but how to check their progress and 

 avoid their return. There are figures and descriptions of the weeds 

 pecdiar to various habitats, and of the tools designed to keep them 

 m cheok ; recipes for weed-killers ; a chapter on the principles of seed- 

 testing; the opinions of authorities on the worst weeds of certain 

 districts; lists of literature dealing with various aspects of the subject; 



