162 
Analyses of the Ashes of Plants. 
Wheat, peas, white mustard-seed, and turnip-seed were se- 
lected as non-silicious ashes for trial : — 
Plios. Acid. 
1000 grains of wheat burnt in the nsual way 
afforded . . . . . . G'14 
1000 grains digested in nitric acid and subse- 
quently burnt gave . . . . .6*34 
It is to be observed, as all chemists will at once understand^ 
that the estimation of phosphoric acid does not admit of such 
perfect accuracy as that of other substances, as that of sulphuric 
acid for instance. A greater amount of latitude must therefore 
be allowed for the results in this case than in that of the acid just 
described. 
Turn{j)-seed. 
Phos. Acid. 
1000 grains of turnip-seed burnt in the usual way gave . 12' IG 
1000 grains of turnip-seed digested in nitric acid and 
then burnt gave 
White Peas. 
1000 grains of peas burnt in the usual way 
gave ...... 
A second experiment on the ash of this 
burning ..... 
1000 grains of white peas digested in nitric 
acid for some time and then burnt : — 
First burning. 
1st analysis , . . . . 
2nd „ 
3rd „ 
2nd experiment — 1000 grains of peas dis- 
solved in nitric acid and burnt :■ — 
1st analysis . . . , • 
2nd „ 
12-56 
4-810 
mean 4-892 
Phos. 
4- 975 
5- 000 
5-065 
mean 5*010 
4- 950 
5- 025 
mean 4-987 
3rJ experiment — 1000 grains of peas dissolved in nitric 
acid and the action maintained till perfect oxidation 
was produced. The materials took fire spontane- 
ously whilst evaporating at a low temperature . 4-800 
Another experiment on 1000 grains of peas perfectly 
oxidated by nitric acid gave . . . .5-08 
White Mustard-seed. 
1000 grains of white mustard-seed burnt in the usual 
way gave . . . . . . .18-32 
