4'2 On the supposed Change 



page 268 he says, the winters in Virginia are very shorty 

 continaing not above three or four months, of which thir- 

 ty days are seldom unpleasant weather ; all the rest be- 

 ing blest with a dear air and a bright sun. However, 

 sometimes the frost is very hardy but it rarely lasts more 

 than three or Jour clays ^ before the wind changes. The 

 rains, except in the depth of winter, are extremely re- 

 freshing and agreeable.... /;o;2d Edit. 1722. 



It appears to me extremely unphilosophical to suppose 

 any considerable change in the annual heat or cold of a 

 particular country. We have no reason to suppose that 

 the inclination of the earth's axis to the plane of its orbit 

 has ever been varied ; but strong evidence to the contra- 

 ry. If this inclination has always been the same, it fol- 

 lows- that the quantity of the solar rays, falling annually 

 on a particular country, must have always been the same. 

 Should these data be admitted, we are led to conclude 

 that the general temperature of every climate, from the 

 creation to this day, has been the same, subject only to 

 small annual variations, from the positions of the planets 

 in regard to the earth, or the operations of the element of 

 fire in the globe and its atmosphere. 



The real truth seems to be, that when a country is cov- 

 ered with forest, the vibrations in the temperature of the 

 rir and of the earth near the surface, are less numerous 

 and less considerable, than in an open country. Dr. Wil- 

 liams himself has furnished the data by which to deter- 

 mine this point. In 1791 he found an open field froze 

 to the depth of three feet five inches ; at the same time, 

 in a forest, he found the temperature of the earth, to be 

 39° by Farenheit, seven degrees above frost. This, fact 

 solves the question here discussed. 



While a country is covered with trees, the face of the 

 earth is never swept by violent winds ; the temperature 

 of the air is more uniform, than in an open country ; the 

 earth is never froze in winter, nor scorched with heat in 

 summer ; and snow that falls in November usually lies 

 till March or April, altho the earth below is not froze, but 

 gradually melts the snow and absorbs the water. On the 

 other hand, an open country is exposed to violent winds 

 and frequent gi'eat changes of weather. The earth in 

 winter is usually froze into a solid mass from one to three 



