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 a huudred 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 hati'ed 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 luiigs 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 

 maj' thus send off 440 gallons per day. At all events the amount 

 transpired by a tree is large — that of a 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 

 cohirans above — and being cool, necessarily compels precipitation on 

 reaching a warmer sti'atum of moist air, and rain ensues as soon as the 

 precipitation is sufiicient. 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 i-eservoir 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 oi 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 i)rocess 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 



