iv PREFACE, 
stand-point, and as no pretence is here made to impart 
special chemical knowledge, it is hoped that Mr. Waring- 
ton and the reader also will forgive any slight incursions 
into a territory which the writer has no claim to enter 
except upon sufferance. 
Structural botany, whether dealing with the outer con- 
formation or the internal organization of plants, is only 
incidentally treated of in these pages; the classification 
of plants is also passed over without notice, as not coming 
within the scope of this Handbook. 
Detailed text-books of Botany, or of Vegetable ‘Phy- 
siology, expressly adapted to the requirements of agri- 
culturists do not exist, but there are many works from 
which a comprehensive general idea of the present state 
of knowledge of these subjects may be obtained. 
In the compilation of the following pages the writer 
has availed himself of Van Tieghem’s “‘ Traité de Botani- 
que,” the French translation of Sachs’ ‘“ Physiologie 
Végétale” by Micheli, and Dehérain’s ‘‘ Cours de Chimie 
Agricole,” etc. The works and memoirs of Darwin have, 
of course, been laid under contribution, as well as nu- 
merous scattered papers by various authors. More es- 
pecially the writer has to acknowledge his obligations to 
the voluminous records of the noble series of cultural 
experiments carried out at Rothamsted for so many years 
by Sir J. B. Lawes and Dr. Gilbert. The ‘‘Memorandum 
Sheet” published by these experimenters supplies annu- 
ally a condensed summary of the results of their experi- 
ments, and is a document that should be carefully 
studied with due reference to its professed object, by all 
who have the advancement of agricultural knowledge at 
heart. M. T. M. 
