78 S. W. Johnson on some points of Agricultural Science. 
t 
dences will be brought forward to the same effect. May not the 
influence of lime and guano (or the carbonate of ammonia re- 
sulting from its decomposition,) in some cases be partly due to 
their fluxing the anhydrous or non-absorbent silicates of the soil, 
thus giving origin to absorbent silicates, as well as to their dis- 
placing effect on silicates already existin 
But it is of little use in the absence - decisive investigations 
to saa naane on these topics except for aeeith thie exciting 
Way, Liebig and ees have ss eg observed that phos- 
oric acid is absorbed by soils, the trials of Resleker 
os referred to it “itn appear that among the acids there 
Se nalogous to te established between the 
bases. ‘T'hus in one experiment in which the drainings of a 
manure heap were — through a soil, there were found in an 
imperial gallon 
Before After 
filtration ee the soil. 
“15 
Silica, gag 2°3 
Phosphates of ‘Time and i OR; Se es Ps eee 154 
Sulphate o: wo ¥ 218 2.06 Caen eee 
ar oa He - - - - 1746 - - 79°72 
Carbonat te of magnesia, - - - 12°83 Pye eee I 
‘ae tux bible iad x joa 4:29 
Ohloria of BE on - - . - 22°85 - - - 1890 
“ “ potassium, - - - - 85°25 - * ¢ 26°44 
In another case were found 
Before After 
filtration pensehs the soil. 
* . 15 15-08 
Precptes of — 2 and Time, -  s eees - ©. eee 
phate of lim - « T44°< Mg re trace. 
of te - “5S Se OE - - + 48°48 
= 4.“ polasdiom, - <> ..*)) .oq@OOe bec ce.* -.500m 
Carbonate of potash, - - -  ~- 14869 - - = 85°93 
The entire analyses have not been quoted as I do not now 
intend to discuss these results fully, but merely wish to direct 
attention to the fact that in both imstances silicic acid —— 
only as the result of an excess of carbonate of » n the 
dung-liquor to which the soil was subjected) has a eceodel 
from the soil, and phosphoric acid has been fixed by it, while ia 
ak acit has been retained and — lost by 
