1G4 Annh/srs of the Ashes of Plants. 
:ui(l fully as much of phosphoric acid., was thought very suitable 
for this experiment : — • 
Pliosiilioric Acid. 
1000 grains of barley were burnt in the usual way, and gave 10 "61 
1000 grains dissolved in nitric acid and then burnt gave . 10*19 
1000 grains of another specimen of barley* were burnt in the 
usual way and gave 7*96 
1000 grains of the same barley were charred at a low tem- 
perature and the cliarred mass deflagrated with nitrate of 
barytes ; it gave 7 '52 
Another specimen of barley was burned in the usual way, and 
three analyses of its ash made : — 
1st Analysis, 1000 grains gave .... 10"89 
2nd 1000 .... 10 -50 
3rd ,, 1000 .... 10-50 
1000 grains of the same barley nearly oxidated by nitric 
acid, the acid liquid neutralized by carbonate of soda, and 
afterwards burnt; it gave 10*90 
A specimen of Moldavian barley, which afforded 2 93 per cent, 
of ash, was burned in the usual way — the ash gave 30'08 per 
cent, of phosphoric acid. Another portion was oxidated by nitric 
acid ; the liquid was neutralized by carbonate of soda, and the 
product burned: the phosphoric acid calculated on the ash was 
found to be 29"92 per cent. In this instance the barley was fully 
burned, there being in the ash obtained by the ordinary method 
not more than 3 per cent, of charcoal. It is plain, however, 
that no phosphoric acid had been h)st. 
We do not, then, think it worth while to carry the evidence 
further, with the view of proving that In no form Is phosphorus 
lost in the burning of plants. The discrepancies observable in 
these analyses are such as are Inseparable froin the estimation of 
phosphoric acid, at all times difficult, but peculiarly so in the case 
of plant-ashes ; the differences, too, are often in an opposite sense, 
that is, an ash obtained by the use of an oxidating medium some- 
times gives on analysis rather less than more phosphoric acid, 
evidently due to imperfections in the available methods of de- 
termining tlie quantity of this acid. 
The conclusion we have arrived at is, that In no ]<Ind of plant 
and under no circumstances does the ordinary method of com- 
bustion lead to the loss of phosphorus in any form, provided only 
that a moderate temperature be employed. For any other case 
* These specimens form part of a series ^rown under very different and 
unnatural conditions ; hency the variation in P in the two specimens. 
Tins circumstance we conceived to tit them better I'orour expeiinients. 
