414? The Rev. J. B. Reade's^wr/for Observatiojis 



jialcs deChimie, vol. lxi. p. 187 Both these observers 



conclude that these foreign principles were produced by the 

 organic power of vegetation." Unfortunately, however, these 

 experiments, and others similar to these, though conducted by 

 able naturalists, have as yet failed to gain any very general ac- 

 quiescence in the conclusions which are drawn from them. 

 And this arises from the gratuitous supposition that not only 

 undetected sources of error may possibly have existed, but 

 that the very presence of foreign matter in the ashes proves 

 error to be unavoidable. 



The facts which I have already brought forward, in my 

 former paper, have led me to adopt the conclusion of Bra- 

 connot, and to dismiss, as altogether untenable, any supposi- 

 tion of accidental introduction with respect to the elements of 

 vegetable structure. For, if it is not to be doubted but that 

 the presence of organization is direct evidence of the pre- 

 sence and agency of life, and that every organized portion 

 of a plant is a proper product of the power of vegetation, 

 then it will follow, that the place which the solid materials 

 occupy is an important and an appointed one, and we shall 

 be warranted to say, under a more extended application 

 of Professor Henslow's own remark, that the process of re- 

 spiration prepares the organizable materials*, whether car- 

 bonaceous, siliceous, saline, or metallic, from whose subse- 

 quent elaboration are derived those infinitely varied condi- 

 tions of organized matter which are essential to the develop- 

 ment of the numerous tribes of plants; and here I cannot 

 but add in the eloquent language of this author, that " from 

 these same materials are constructed those organized sub- 

 stances which seem to stand as portals to the intellectual and 

 spiritual world — channels of direct communication by which 

 reason and revelation may tell the frail tenants of a few mould- 

 ering atoms, of that more glorious condition which will as 

 certainly be their heritage hereafter as their hopes and yearn- 

 ings after immortality are within the actual experience of their 

 present state." 



On communicating the nature and result of my experi- 

 ments to Professor Henslow I was gratified by receiving the 

 following reply: " Mr. R. Brown, with whom I have had 

 some conversation upon the subject of your letter, confirms 

 your conclusion that silica enters as an organizable product 

 into the structure of plants, and I have now no doubt of the 

 fact from what you and he have stated, though I had not sus- 

 pected it before. Mr. Brown told me that he had long since 

 made experiments similar to yours, but had never published 



* Principles of Botany, p. 202. 



