vi THE FOOD OF PLANTS 



is wanting in the text. On the whole, however, an 

 experimental course has been developed in the series 

 of lessons. 



The book is intended neither for reading in the 

 study, nor for supplying suitable experiments for 

 the lecture table. The student is supposed to himself 

 perform the experiments under the guidance of a 

 teacher. With this in view, I have taken pains to 

 make the experiments simple, and the materials 

 required inexpensive, so that all classes of schools 

 might find the course of instruction within their 

 capacity and their means. 



A student who has been carefully through the 

 experiments will find that he can read a work such 

 as Fream's book on Agriculture with intelligence. 

 He will not, however, be able to pursue the study of 

 the chemistry of agriculture further, in a thorough 

 and scientific sense, without first mastering the 

 principles at least of chemistry. He should, accord- 

 ingly, be familiar with Eoscoe's Elementary Chemistry, 

 or a work of similar character, before involving 

 himself in the chemistry of agriculture. 



I cannot conclude without thanking Mr. Wallace, 

 Professor of Agriculture in the Edinburgh University, 

 for the valuable assistance he has given me with the 



pr fs - A. P. LAURIE. 



