PROCEEDINGS OF SECTION G. 
may, however, be in favour of the Indian system, 
that it disturbs so little the dead roots which 
are left in the soil. The vegetable matter, which, 
when the land is in a state of nature is left on 
the surface, undoubtedly does much good while 
it lasts by acting as a mulch; while its exposure 
to the sun and air causes it to decay (be oxidised 
or burnt up) far more quickly, and far more 
quickly to yield substances which, carried down 
by water into the soil, help on the changes by 
means of which plant-foods are released from 
potential combinations, than would be the case 
if it were buried. Whether the Indian method 
of leaving the surface vegetable matters where 
they are, or the English system of humefying 
them by burying them and distributing them 
throughout the soil to the depth of about seven 
inches, is the better in the climate of our 
interior should, I think, be ascertained by a 
series of exhaustive comparative experiments. 
It may be found that a compromise between the 
English and Indian systems, by means of which 
the vegetable matter on the surface is only 
buried deeply enough to partially humefy it, 
and is afterwards kept near the surface, while 
the soil underneath is stirred to a much greater 
depth, will prove to be better than either; for 
if we succeed in making the upper three inches 
of the soil to be rich enough in humus and par- 
4 tially humified substances to be sufficiently open 
“=. to prevent the surface from caking, or to act in 
«<* some degree as a mulch, we shall make the rain- 
water we receive to go much further than it 
does at present. I hope, shortly, to be able to 
initiate some experiments for the purpose of 
determining these points. This investigation 
may prove to be closely connected with the 
problem of inducing the soil to give up to crops 
more of its natural potential fertility. 
(3.) Comparative trials of the common turn-over and 
rotary disc ploughs.—Experiments are needed 
in connection with another matter. Within the 
last few years the rotary disc plough has come 
into use, and from the smallness of the cost of 
its ploughing the land, is likely to receive wide 
adoption. As in its method of cultivating the 
