THE ECONOMIC ASPECTS OF SOIL EROSION 
375 
underground and made to do its appropriate work. In the con- 
dition of our ill-organized tillage so large a share of the precipi- 
tation is sent in its destructive superficial Avay that the lower soil 
often lacks the share of moisture which is necessary for the work 
of decay in the underlying rock, and which would be most use- 
ful to the crops in time of drought. 
Although it is very difficult to make a newly overturned soil 
safe from the assaults of the rain, I believe that with a careful 
and in a large way economical S3^stem of tillage it can be done, 
at least provided the inventors can help us over certain me- 
chanical difficulties. In the first place it should be noted that 
the plow, which has been much vaunted as a noble contrivance, 
is as ordinarily used an instrument which most effectivel}" serves 
to compact the earth, so that when the few inches of ground 
tilled become soaked with water the fluid cannot penetrate into 
the deeper part of the earth. The reason for this injurious action 
can readily be understood. The pressure of the foot of the [flow, 
due to the counter -thrust of the force used in dragging it forward 
through the earth as well as to the weight of the instrument, 
serves in a very effective way to compact and smear the surface 
over which it passes. When the frost penetrates deepl.y, the 
heaving action which it effects operates in a measure to overcome 
this effect of the jdIow, but in almost all fields, especially those 
of the southern part of this country, the artificial hard-pan is to 
the skilled eye most evident. It needs but a comparison of a bit 
of land which has been long under the plow with a like area 
still in virgin forest to show the true measure of this action. 
The one is for a few inches in depth moderately open, but at a 
lower level is so hard that water can penetrate it only in a slow 
way ; the other is open-textured to so great a depth that the rain 
and roots can penetrate in most cases to the rock which has not 
yet been broken up. 
There is needed an instrument which will turn the soil in 
the manner of the spade, a tool which does not pack the under 
earth, but leaves it in a position very favorable to the downward 
movement of the water. As my friends who know tlie nature 
of meclianics tell me that it will be dillicult to make such a con- 
trivance, we ma^' have to content ourselves for a considerable 
time to come with the ancient, but to 1113'^ mind by no means 
venerable, utensil which has alreadv Pent the substance of mil- 
lions of men to the sea. There are ways of using the plow l>v 
which its evils may be minimized. In the first place, the tilth 
