178 ORIGIN OF ORGANIC MATTER 



a recognition injurious to scientific inquiry. The imperfect expe- 

 riments which have been made with a view of deducing certain 

 phenomena in the living organism from some simple physical law, 

 or bringing them into harmony with some ordinary experimental 

 fact, although these phenomena probably depend upon a sum of 

 many individual forces acting under the most various modifications, 

 simply afford evidence of the superficial and deficient physical and 

 chemical attainments of those who instituted them, and have pro- 

 bably done more to support the belief in a vital force, than the fact 

 that we have as yet no prospect of being able to refer the forma- 

 tion of cells and tissues, and the suitable conformation of all the 

 individual parts of the animal organism to definite physical and 

 chemical laws. 



ORIGIN OF ORGANIC MATTER IN THE VEGETABLE KINGDOM. 



BEFORE we proceed with our general review of zoo-che- 

 mical processes, we must consider the locality and the relations 

 under which organic matter is mainly formed. Theoretical che- 

 mistry shows us that the composition and all the properties of 

 those substances which are especially named organic, are not only 

 not opposed, but actually afford the most brilliant confirmation of 

 all the more general laws which refer to this department of 

 chemistry. There seems, therefore, considerable probability that 

 the formation of organic matter from inorganic substances may 

 be due to the action of the more general laws of physics and 

 chemistry. If affinity, like gravitation, be an integral property of 

 matter, the first indications of the formation of organic matter 

 must necessarily furnish the best point from which to investigate 

 the chemical laws which control the generation of organic from 

 inorganic substances. The relations on which such formations 

 depend have not, however, been examined with sufficient exactness 

 to admit of our representing the formation of organic matter by 

 simple formulae, based upon direct observations. Whilst an 

 opinion prevailed in earlier times that plants, like animals, required 

 for their well-being to appropriate to themselves at least some 

 definite, but not inconsiderable, amount of organic matter in the 

 form of humus, Ingenhouss held the opinion that plants derive 

 their nutriment solely from inorganic nature ; and this view has 

 been most ably defended by Liebig, who has shown that the 



