72 Q U A R T E JR I, V J O U R N A L . 



phenomena of light and heat, the rays of the solar spectrum. An- 

 other of still more importance treats of the tithonic ray^ or the 

 chemical rays of former writers. These essays are well illustra- 

 ted, and the peculiar doctrines supported by numerous well de- 

 vised experiments, the manipulations and arrangements of which 

 are neatly demonstrated by diagrams on copper. Of the first part 

 we feel bound to say that it is written in philosophic language, 

 that it bears the impress of a philosophic mind, and that an air of 

 importance and originality appears throughout the whole produc- 

 tion, and that even the commonplace ideas are so well expressed 

 that they bear the aspect of new thought and original suggestions. 

 It may truly be called a labored treatise, a well-wrought- produc- 

 tion abounding in valuable matter, which, though it cannot be 

 claimed as original or new, still, the labor expended in putting to- 

 gether the materials, entitle the author to a share of the credit 

 which is awarded to originality. 



Having expressed our views of the general merits of the work, 

 we proceed to notice some of the doctrines which Prof. Draper 

 has expressed, and which he has attempted to maintain. We must 

 premise, however, that of these doctrines we find it necessary to 

 make a selection, and to confine ourselves within narrow limits, 

 for it is impossible to notice, even summarily, all the opinions and 

 doctrines which are expressed in the first part of the work. The 

 treatise is introduced with some general views of the influence of 

 physical agents on organization and life, in which he has given 

 brief expositions of the nature of organized combinations, the 

 changes which are efTected by physical laws, and how they effect 

 the extinction of living races, also on the relations of organized 

 forms to the atmosphere, and closing with a notice of that law 

 which secures or which emancipates the higher races from the di- 

 rect dominion and action of external agents. Prof. Draper, in 

 the second section of the introduction, takes this early occasion to 

 express his decided dissent from the views "entertained by many 

 physiologists in legard to the existence of a vital force. As this 

 is one of the leading doctrines of the work, we shall extract the 

 passage in which he announces his views. 



" In this work the existence of the Vital Force of physiolo- 

 gists — as a homogeneous and separate force — is uniformly denied. 

 Tiio progress of science shows plainly that living structures, far 



