Anah/scs of the Ashes of Plants. 
1G7 
grains of heated common salt ; the mixture when gently heated 
lost 15'54, heated still more it lost 1 6 • OS, perfectly fused lG-41, 
or 62' 10 per cent, on the microcosmic salt. 
The smell of hydrochloric acid was very distinct, and moistened 
litmus-paper held over the capsule was reddened by the fumes. 
The fused salt dissolved in water gave a pure white precipitate 
with nitrate of silver, showing that it had not assumed more than 
one proportion of soda from the chloride. 
Microcosmic salt loses its ammonia at a low temperature ; a 
little additional heat will then drive off its equivalent of basic 
water. It might be thought that the loss of chlorine in this ex- 
periment was attributable to the ammonia (as in the instance 
before given of the ammonio-phosphate of magnesia), but it was 
evident that the chlorine escaped as hydrochloric acid, and it 
would seem that the basic water is retained until the heat becomes 
sufficient to effect this change. It is plain that phosphates cannot 
decompose the alkaline chlorides otherwise than by the help of 
the water which they contain ; and there is good reason for 
believing that in the burning of plants this water is dissipated 
by the heat long before the mineral substances of the ash can 
have been brought in sufficient contact to enable them to act upon 
each other. 
In order to decide by actual experiments the liability to loss 
of chlorine from the two first causes, that is to say, fiom vola- 
tilization in the early burning, or by the subsequent action of the 
phosphates of the ash, the following experiments were made : — 
A specimen of turnip was dried and powdered. 
424 grains of this specimen were burned to ash in the usual 
way, and at fully the temperature ordinarily employed by us in the 
preparation of ashes. 
The ash Avas dissolved by nitric acid and water, filtered, and 
precipitated by nitrate of silver ; the chloride of silver weighed 
!• 55 grains, equal to "382 chlorine, or '0901 per cent, on the 
dry turnip. 
A second quantity of 424 grains of turnip was charred at a very 
low temperature in a covered platinum vessel ; the charred mass 
was powdered, treated with boiling water and a few drops of nitric 
acid, and thoroughly washed. The washing occupied much time 
and required a large quantity of water. The chlorine was pre- 
cipitated by nitrate of silver; the chloride of silver weighed 1*69 
grains, equal to -417 chlorine, or • 0983 per cent, on the dry turnip. 
This particular turnip contained 10-5 per cent, of ash, so that 
the comparative results may be thus stated : — 
On tlie Dry Turnip. On the Asli. 
Chlorine by c/<a?Tt/z^ .... -0983 per cent. '937 per cent. 
,, by burning to ash . . . '0901 '859 ,, 
