110 PROCEEDINGS OF THE CANADIAN INSTITUTE. 
three trees, left by accident, had sold for a thousand dollars, showing 
that the field would have sold for # hundred thousand dollars—a field 
which, in its whole cleared day till now has never given a thousand 
profit. Much land through the Province might well have been spared 
the axe. and yet enough been given to the field. But we cleared 
without method or order, each thinking the more he cleared the 
richer he grew, till a deadly hatred of trees. seems to have pervaded 
the community, and their destruction was considered equally pat- 
riotic and beneficial. It is found, however that we have been under 
a great mistake, and that a country will grow more grain and cattle 
and produce them easier when one-fourth is left in woods interspers- 
ing the rest than when all is cleared.. The reason of this is evident 
to all who consider the structure of a tree, which I will ask you to 
notice. Every tree draws its nourishment from the soil near its roots. 
It is carried upward by means of a large quantity of water, which 
passes with it to the leaves—the lungs of the tree. Here it is ex- 
posed to the air, changes occur, the food goes to its place in trunk, 
branch, or leaf, the water passes off into the air. It is said one oak 
may thus send off 440 gallons per day. - At all events the amount 
transpired by a tree is large—that of « forest immense. This -passes 
upward to the atmosphere—it is said that if it could be tinted the 
wood below would form no proportion in size to the vast coloured 
columns above—and being cool, necessarily compels precipitation on 
reaching a warmer stratum of moist air, and rain ensues as soon as the 
precipitation is sufficient. The forest is the great local cause of the 
showers which fertilize the spring and summer fields. The next great 
benefit to agriculture is the reservoir they form for water. Their bed 
is deep, loose, porous, a mass of decayed leaves, intersecting roots, 
and forest soil, which holds in reserve great quantities of water (which 
otherwise would flow rapidly off over the fields), and feeds therewith 
the innumerable underground channels which keep moisture in the 
soil. Once we got water by digging seven o1 eight feet in many 
places ; now we must go forty or fifty. As land is too much cleared 
the springs recede from the surface, and the process goes on, where 
allowed, till it becomes a desert where no blade of grass can grow. 
In history countries are known to have been rich and fruitful, to have 
been deprived of their due amount of trees ; to have become sterile 
and be abandoned by their population ; to have been sufficiently re- 
planted, to have recovered their lost watercourses and their vanished 
