346 Chemical Changes in the Fermentation of Dung. 
Comparison of the Composition of Coiu's Urine Fresh, and after it has heen 
kept a Month exposed to the Air. — (Stephens, vol. i. p. 485.) 
Fresh. 
A Mouth 
Old. 
Urea along with some resinous colouring matter 
92 
G24 
95,442 
4 
000 
1,000 
10 
100 
40 
Benzoic acid (hippuric acid) 
Combined with 
90 
250 
potash, soda and 
516 
500 
loss 16 
ammonia form- 
256 
165 
ing salts. 
1 
205 
487 
GC4 
G64 
554 
554 
405 
338 
loss 67 
70 
26 
loss 44 
272 
272 
65 
2 
36 
22 
2 
0 
4 
1 
1 
0 
36 
5 
Sulphuretted hydrogen 
1 
Sediment, consisting of phosphate and carbonate of) 
lime, and magnesia, alumina, silica, and oxide of > 
180 
100 
,000 
99,9.50 
The occurrence of .51G jarts of lactic acid in this tahlc is calculated to 
shake our faith in it, for Licbig denies the existence of this acid in urine, and 
the substances grouped under sediment utterly defy calculation. It does not 
appear what portion of each base is in combination with each acid. I quote 
it for the remarkable loss of sulphitric and phosphoric acids and for the guide 
to one loss in the presence of the sulphuretted hydrogen. 
XVII. — On the Retention of Moisture in Turnip-Land. By 
Robert Vallentine, Burcott Farm, Leighton Buzzard. 
Prize Essay. 
The great value of good root crops is now so generally appre- 
ciated, that no special pleading is here required to prove the fact. 
Tlieve are few light-land farmers who do not know that root crops 
form the very foundation of corn crops ; and that without turnips 
less manure would be made, less corn grown, fewer cattle and 
sheep kept, and, as a natural consequence, less profit realized. 
Moist climates, such as those of Scotland and Ireland, stand 
pre-eminent for producing heavy root crops ; that of England 
may be taken as a medium between a moist and a dry climate 
