VARIOUS METHODS OF ANALYSING ASHES. 
365 
EXAMINATION OF THE VARIOUS METHODS OF ANALYSING 
ASHES. 
In a paper entitled " Fundamental Experiments on the Deter- 
mination of the Inorganic Constituents of Organic Bodies," M. 
Strecker has submited to criticism the methods proposed by Rose 
and Erdmann for the analyses of ashes. According to Rose, we 
must distinguish in organic substances between teleoxidic, mero- 
oxidic and anoxidic inorganic constituents. Strecker found, in his 
experiments, that inorganic constituents could not be extracted by 
water and acids from the cinder of the charred organic substance, 
even with artificial mixtures of charcoal and various substances, 
when they were contained therein in comparatively small quanti- 
ty ; but, on the other hand, they were completely extracted when 
present in larger quantity. Now this behavior accords with that 
ascribed by Rose to anoxidic substances ; they contain small quan- 
tities, of inorganic constituents, whilst the teleoxidic, as for in- 
stance urine, bones, &c, contain large quantities. Now the same 
is the case with the ashes of plants ; and Strecker is therefore of 
opinion, that the reason why the inorganic substances are some- 
times entirely removed by water and acids from the charred mass, 
and at other times only in part, is owing solely to the proportion 
of the ash to the cinder, and not at all to any peculiar kind of 
combination of the inorganic substances with the charcoal. 
Strecker then draws attention to the circumstance, that we must 
not suppose, from the presence of alkaline carbonates in the aque- 
ous extract, that they are always derived from salts of inorganic 
acids with potash, since tribasic phosphate of potash, after cal- 
cination with sugar, yields carbonate of potash to water.* Strecker 
also observed the production of cyanides and sulphurets on fol- 
lowing Rose's method, which may give rise to slight errors in the 
analysis. There is also a loss of chlorine according to Rose's 
* Does not the formation of alkaline carbonate, when organic matter is 
heated with tribasic alkaline phosphate, show in opposition to the state- 
ment of Liebig and other chemists, that tribasic phosphate cannot exist 
in the animal fluids ? otherwise alkaline carbonate should be contained 
in the ash, which they found not to be the ease. — Ed. Chem. Gaz. 
29* 
