50 MODERN FOREST ECONOMY. 



excess of '991 inches. The experiment was repeated with 

 similar results. By another experiment it was ascer- 

 tained that while the deposit of dew on a green surface 

 amounted to 4*75, that on a white surface amounted only 

 to 2, or less than half the quantity. He further ascer- 

 tained that while the .difference of temperature in the 

 water in the two jars employed in the former experiment 

 was only a few degrees, the difference of temperature 

 between black ground and ground shaded by bush was 

 about 25 degrees Fahr., which would occasion a vastly 

 greater difference in the amount of evaporation than that 

 which occurred in his experiment. In illustration of what 

 is implied in the result of the experiment made by Mr 

 Blore, the excess of evaporation from the more exposed jar 

 above that from the jar partially shaded, but not covered, 

 being an inch, more strictly, upwards of ninety-nine hun- 

 dredths of an inch, of water, and more than double that of 

 the latter, Mr Blore remarks : 'An inch in six days (the 

 time consumed in that experiment) will give for 102 days, 

 the ordinary duration of the hot, windy, and dry season in 

 the district, 17 inches. This is equal to about three hun- 

 dred and eighty-four thousand (384,000) gallons per acre, 

 and supposing 1000 acres had been burned, blackened, and 

 dried, what with sunlight, fire, heat, and wind, the evapora- 

 tion would be an excess of three hundred and eighty-four 

 millions (384,000,000) of water above what would have 

 been evaporated if the bush or grass had been left un- 

 burned.' And I add, a fortiori, if the forest had not been 

 destroyed, 



SECTION C. FLOODS, INUNDATIONS, AND TORRENTS. 



It may be more difficult to prove to the satisfaction of 

 all that devastating inundations which occur from time to 

 time in countries on the Continent of Europe are conse- 

 quence of the extensive destruction of forests, than it is to 

 prove that the scarcity of timber and firewood from which 

 many has suffered is attributable to that, and that desicca- 



