558 



Miscellaneous. 



himself, and assert, that that man acts like a blockhead who treats 

 other sciences with contempt in proportion to his ignorance of them. 

 Whoever has read the publications of Dutrochet, Mohl, linger, 

 Goppert, &c., will certainly confess that they know quite as much of 

 chemistry as can be required from persons who do not profess that 

 science ; and that in those writers no such absurd theories are found 

 as the nonsense about alternate layers of starch and wax protecting 

 one another reciprocally against the influence of water and ether. 

 As to their knowledge of physics, I think they have a much greater 

 share of it than Dr. Liebig, as is evidently proved by his Theory of 

 the Winds. 



Dr. Liebig thinks that all the talents of vegetable physiologists 

 have been wasted in a study of the structure and formation of plants, 

 and that they have proceeded in this task without consulting che- 

 mistry and physics. I confess that our physiologists, in their ignor- 

 ance, have always been such simpletons as to think that a person 

 must first be perfectly acquainted with all the parts of a machine — 

 with its wheels, levers, &c., before he can expect to be able to explain 

 its action in any reasonable way. I do not doubt that they are also 

 of opinion, that if Dr. Liebig had only had a small idea of the struc- 

 ture and physiology of plants, he would have avoided expressing 

 himself as he has done in speaking of the milky juice ; or, as at p. 66, 

 where he says : " The vegetable physiologist considers a leaf in 

 every case only as a leaf, notwithstanding that a leaf, which pro- 

 duces oil of turpentine, must be of a different description from that 

 which gives oxalic acid." A leaf is indeed always a leaf. But the 

 physiologist has ascertained, by the anatomy of plants, that neither 

 leaves nor stems of themselves produce oil, or any other matter, and 

 that these are formed only in separate cells. It is indifferent whe- 

 ther these cells occur in the leaves or in the stem. To explain these 

 processes, it is of the greatest importance to investigate anatoniically 

 the most minute portions of the cells ; for the productive power of 

 two cells, placed near one another in the same leaf, differs frequent- 

 ly much more than that of two plants distant from one another, and 

 quite different in their habits. If Dr. Liebig had the least notion of 

 a microscope, and its use, he would not have exposed himself to 

 ridicule by his idle objections to the existence of fungi producing 



