1913] CURRENT LITERATURE 155 
itself remain acid. And not only so, but the important process of nitrifica- 
tion, carried on by bacteria whose activity is closely connected with the amount 
of lime available, is seriously retarded. Leaves become yellow and there is 
a general nitrogen starvation of all vegetation. 
It developed during the course of the investigation that the addition of 
lime to such soils, even though it improved materially the conditions for plant 
growth, reduced the acidity only one-third. This result, taken together with 
the fact that an acid soil need not contain free acid, and the further fact that 
forest trees do grow on acid soils, makes it plain, in the opinion of the author, 
that lime is valuable, not because it neutralizes acids, but because it furnishes 
a substance indispensable to normal plant growth. The conclusion thus 
reached points definitely to the use of lime as a means of combating smoke 
injury to vegetation and of rendering denuded areas again able to support 
plant life. 
A supplementary investigation of the effect of metallic poisons in the soil 
showed that the sensitiveness of plants to these poisons varies greatly. It 
was found possible to arrange a complete series, leading from those which were 
seriously affected to those whose growth was definitely improved.—D. H. 
ROSE 
The living plant 
It is with some interest that plant physiologists and ecologists will read 
GANoNG’s new book on The living plant. It is the first attempt in English 
to bring, in a comprehensive way, the main findings of these subjects within 
reach of the layman. The aims of the volume are well stated in the first 
paragraph of the preface: “It is not designed as a digest of our present scien- 
tific knowledge of plant physiology for the use of experts in the subject, but, 
in conformity with the aim of the series of which it is a part, it seeks to present 
to all who have interest to learn an accurate and vivid conception of the princi- 
pal things in plant life. I was once myself such a learner, and I have tried to 
write such a book as I would then have delighted to read. It is, in a word, 
an attempt at that literature of interpretation which was forshadowed by 
Francis Bacon in the fine passage that stands on its dedicatory page.” 
Aside from the general interest in plants, we have at present a rapidly 
growing interest in agriculture. This makes the issue of the present clear 
statement of the principles of plant production especially timely. In this work 
the author has lived up to his high reputation as a teacher. One is surprised 
at the clearness and vividness with which he sets forth the main features of 
plant activity. Aside from presenting the main findings of the subject, the 
author gives a clear insight into the scientific method in action, for repeatedly 
he shows the processes by which the conclusions have been reached. He 
likewise makes clear the large cosmic relations of the subject. 
*Ganonc, Wiitiam F., = living plant. 8vo. pp. xii+148. figs. 178. New 
York: Henry Holt & Co. 19 
