1847.] Wood's Class Book of Botamj. 99 



attachment to him as the great master in botany, the nahiral 

 method made slow progress. There were two intrinsic difficul- 

 ties in th€ M'ay, which could be removed only by long continued 

 exertion of a host of the finest minds. These difficulties are not 

 indeed all removed. The ignorance which nearly overwhelmed the 

 powers of the great Linna?us is not yet wholly dispelled, and so 

 oppresses the great lights of botanical science, that they are 

 obliged still to retain not a few artificial characters. How they 

 are to be removed no eye has yet discovered, though the rapid 

 improvement made in the last twenty years gives rich promise of 

 a brighter day. 



Mr. Wood, taking the natural system in its most improved 

 state, has given to the student a very clear exhibition of its prin- 

 ciples, as well as a brief view of the Linnaean classification. In 

 the second edition he has added a chapter on the "principles of 

 agricultural chemistry," which supplies to the learner an impor- 

 tant part in the practical application of the science. Among the 

 elements of plants is carbon, which he correctly states " is de- 

 rived from the carbonic acid which the atmosphere contains, 

 and from the decaying vegetable matter of the soil;" thus, mak- 

 ing the sources of carbon to be the " air, earth and water." The 

 use and benefit of manures is thus fully implied, and on no other 

 principles can he maintained. 



In the study of the natural system no learner knows how to be- 

 gin. Though he may readily discover the great natural divisions, 

 and see that his plant is, for example, an exogen with a polypeta- 

 lous corol, as there are before him seventy orders with polypeta- 

 lous corols, how shall he refer his plant to the proper order? In 

 the second edition this is done by an analytical table; a table for 

 the analysis of plants, preceded by a clear exposition of the course 

 to be pursued, in which the Linnaean system is not employed, and 

 by which the student is led by a simple process to the order in 

 which his plant is contained. This process of analysis " consists 

 of a simple series of dileramas or alternatives ; the decision being, 

 in almost all cases, to be made merely between two opposite or 

 obviously distinct characters.^' This mode of analysis avoids all 

 the irregularities found in the Linnaean classification, shortens and 

 simplifies the analysis, and conducts the pupil by obvious and dis- 

 tinct particulars to the natural family now sought after. If the mode 

 of this general analysis is as complete as it appears to be, it is 

 one of the greatest improvements found in any class book, or other 

 book, on this modern science. It realises the- declaration once 

 made, that ere long the dependence on stamens and pistils, so 

 complete for fructification, will be unknown in the study of 

 botany. Rendering useless as it does the artificial system, it will 

 not however detract from the glory which must ever rest on the 



