CHAP, v.] the Influence of the History of Development. 1 89 



of general botany, which appeared first in 1842-3, and in much 

 improved editions in 1845 and 1846, and in two subsequent 

 years. The difference between this and all previous text-books 

 is the difference between day and night ; in the one, an 

 indolent carelessness and an absence of ideas ; in the other, 

 a fulness of life and thought, calculated to influence young 

 minds all the more, because it was in many respects incom- 

 plete and still in a state of fermentation. On every page of 

 this remarkable work, by the side of facts really worth know- 

 ing, the student found interesting reflections, a lively and 

 generally coarse polemic, and praise and blame of others. It 

 was not a book to be studied quietly and comfortably, but one 

 that excited the reader everywhere to take a side for or against, 

 and to seek for further instruction. 



The work is generally quoted as ' Grundziige der wissenschaft- 

 lichen Botanik,' but its chief title is 'Die Botanik als inductive 

 Wissenschaft,' which indicates the point on which Schleiden 

 laid most stress. His great object was to place the study, 

 which had been so disfigured in the text-books as scarcely 

 to wear the semblance of a natural science, on the same foot- 

 ing with physics and chemistry, in which the spirit of genuine 

 inductive enquiry into nature had already asserted itself in 

 opposition to the nature-philosophy of the immediately pre- 

 ceding years. It may seem strange to us now to see a 

 text-book of botany introduced by a formal essay, 131 

 pages long, on the inductive method of investigation as 

 opposed to dogmatic philosophy, and to find the principles 

 of induction set forth again and again in connection with 

 a great variety of subjects in the book itself. Many objec- 

 tions may be raised to the contents of this introduction ; it 

 may be said that many philosophical dicta are misunderstood in 

 it ; that Schleiden himself has frequently offended against the 

 rules there laid down, for instance, when he substitutes a 

 formative impulse (nisus formativus) for the vital force which 

 he rejects, which is only introducing vital force again under 



