2 Prof. H. Rose on the Inorganic Constituetits 



to show the manner in which the iron is combined with the 

 other constituents of the blood. But these and some other ex- 

 periments of the same kind form isolated examples ; at least it 

 has never been attempted to ascertain the changes which the 

 inorganic constituents supplied to vegetable and animal bodies 

 by the soil and articles of food undergo within them. 



Some time since, I endeavoured to prove, that when an 

 organic substance of vegetable or animal origin is carbonized 

 with exclusion of the air, by not too great a heat, the inorganic 

 constituents can partly be extracted by the ordinary solvents 

 of inorganic salts — water and muriatic acid, but that a portion, 

 and this frequently the largest, exists in the carbonized residue 

 of some organic substances in such a state as completely to 

 resist the solvent action of water and muriatic acid, and can 

 only be obtained by burning the carbonized mass in oxygen 

 gas or in atmospheric air*. This portion of the inorganic 

 matters undoubtedly does not exist in the organic substance 

 in the state in which it is obtained after the incineration, nor 

 even in the carbonized mass obtained from it, but it has been 

 formed by oxidation. I also described several experiments, 

 which showed that the presence and the nature of the car- 

 bonized mass could not be the causes of the insolubility of the 

 inorganic substances in the solvents, even if they pre-existed in 

 the organic bodies in the same state as that in which we find 

 them in the ash. 



These remarks, which I published in an imperfect state 

 and supported by few proofs, for the sake of directing the 

 attention of chemists to this, as it appeared to me, not unim- 

 portant subject, have not received any attention. Since that 

 time, I have, however, occupied myself with these investiga- 

 tions, and have induced several young chemists in my labora- 

 tory to determine the inorganic constituents, with a view to 

 separating those which exist already formed in organic bodies 

 from those which must be contained in them in an unoxidized 

 or less oxidized state. 



These investigations have completely confirmed the view I 

 had arrived at from reflecting upon this subject. In fact I 

 may assert, that in none of my chemical investigations has 

 experiment so completely confirmed the hypotheses which I 

 had made before the commencement of the undertaking than 

 in these. 



When we minutely trace the entire process by which plants 

 and animals assimilate the inorganic substances consumed, it 

 appears that this is effected in the two cases in an entirely op- 

 posite manner. I shall now investigate this more minutely, 

 * Chem. Gaz., vol. v, p. 158. 



