14i 
Effects of different Manures on the 
mixed herbage, they generally increase the produce of Gramina- 
ceous ones but little, and that of Leguminous ones very charac- 
teristically. It has been found, too, that even in a clayey soil, the 
constituent of mineral manures which seems to have the most 
influence upon the growth of the Leguminous plants of rotation, 
beans and clover for example, was potass ; and we have in the 
results under consideration a stiiking instance of the effects pro- 
duced on the growth of the allied plants of the mixed herbage 
bv a liberal supply to the soil of that constituent. Thus, Plot 9 
had in every previous year of the experiments received the same 
description and amount of mineral manure as Plot 8, but in 1862 
the potass was excluded (from Plot 9), and a larger amount of 
soda-salt substituted. The result was that the produce of Plot 9, 
without the potass, gave only 18 instead of 24 per cent, of Legu- 
minous herbage, or only three-fourths as high a proportion as 
that of the plot manured otherwise similarly, but with the potass 
in addition. 
Sujierphosphate of lime alone, used for a series of years, has 
somewhat increased the amount and proportion of the grasses, 
at the expense of the Leguminous plants ; the proportion of the 
Miscellaneous herbage remaining about the same. Still, the 
propoi tion of the Leguminous herbage under the influence of this 
manure, though considerably less than without manure, and little 
more than one-tenth as great as with the mixed mineral manure 
(containing salts of potass, soda, and magnesia, as well as super- 
phosphate of lime), was considerably greater than in any case 
where either ammonia-salts or nitrates were used, whether they 
were employed alone, in combination with mixed mineral, or 
with farmyard-manure. 
Lastly, ammonia-salts alone (or with only sawdust in addi- 
tion), or nitrate of soda alone, considerably increased the propor- 
tion of the grasses, almost excluded the Leguminous herbage, 
reduced the proportion of INIiscellaneous plants, and also the 
total number of species. 
It will perhaps be remembered that some years ago Baron 
Liebig stated he had obtained marked effects by the use of saw- 
dust as a manure ; a result which he considered due to the 
evolution of carbonic acid from the decomposing sawdust, by 
means of which the supply of mineral constituents within the 
soil was rendered more rapidly available. 
We have, therefore, for some years past, applied 2000 lbs. of 
sawdust per acre, per annum, to a few of the experimental plots. 
Where, in previous years, the sawdust was used alone, with 
mineral manure without ammonia-salts, or with ammonia-salts 
without mineral manure, some, but generally a very small increase 
of produce, has been the result. But where the sawdust has been 
