Phosphatic Manures for Root-Crops. 
65 
drill IS the most economical, efficient, and rational mode of incor- 
porating: turnip-manuro with the land. 
30, Purely mineral superphosphates fail to produce good 
turnip-crops on light sandy soils. 
3j.. Superphosphate cannot be considered as the cause of the 
diseases to which roots are liable. 
32. Roots grown on poor sandy soils exclusively with super- / 
phosphate nevertheless are liable to become diseased, or to fail 
altogether. 
33. The deficiency of lime, organic matters, and especially 
potash in sandy soils, accounts for the difficulty of growing good 
roots on such land with purely phosphatic manures. 
34. On light soils turnips should always be grown with, at 
least, some farmyard manure. 
35. Bone-dust, partially dissolved by acid, is a better manure 
for turnips on light land than a purely mineral superphosphate. 
36. On light land a mixture of equal parts of guano and super- 
jiliosphate is better turnip-manure than either manure applied 
alone. 
37. Liquid manure is very beneficially applied to root-crops on 
light land. 
38. An excellent plan of applying bone-dust to the turnip-crop 
on light land is to ferment it with dung. 
39. This is best done by putting alternate layers of dung and 
bone-dust in a heap three or four months before turnip-sowing 
begins, and to turn the heap about a month before it is distributed 
on the field. 
Boyal Agricultural College, Cirencesier, January, 1863. 
IV. — On the Utilisation of Toion Seicar/e. By J. B, Lawes, 
F.R.S., F.C.S. 
No one can read the evidence given before the Select Committee 
" On Sewage of Towns," appointed by the House of Commons 
last Session, without being struck with the great differences of 
opinion elicited during the examination of the witnesses. Whilst 
one and all agree that sewage is a most valuable manure, con- 
taining every constituent necessary to be applied to the land for 
our crops, they differ in a remarkable degree both as to the 
commercial value of a given amount of sewage, and as to the 
quantity requisite to be applied to a given area of land. 
One witness who had been engaged for years In the applica- 
tion of sewage, and whose evidence is said in the " Analysis of 
Evidence" to be "entitled to great weight," gave it as his 
VOL, XXIV. F 
