TEMPERATURE OF SOILS. 231 



Labor, directed witli intelligence, or guided by a full knowledge of factSj may overcome 

 great and serious dillicultios. 



Each district is underlaid by rocks unknown in tiie otliers, and which in each case have 

 something peculiar. Thus the Highland district is underlaid by primary rocks ; the 

 Eastern district, by the taconic rocks ; the Third district, by rocks of the Champlain divi- 

 sion ; the Western, by the Ontario and Helderberg divisions ; the Southern, by the shales 

 and sandstones of the Erie division ; the Atlantic, by sea sands. In each there enters some 

 gelogical element, and this modifies the respective productions of the district. The clas- 

 sification is also geographical, and hence con\ enient for reference ; and the gcograi)hy too 

 has its intluence, which is clearly seen in the length of the winters of the northern, when 

 compared with the middle and southern parts of the State. Height is another element 

 that must not be lost sight of. Climate, which is intimately connected witii elevation, is a 

 complex condition, and must also be studied as one of the controlling conditions affecting 

 the husbandry of the State. 



VI, TEMPERATURE OF SOILS. 



As the atmosphere has its own climate, so the soils have theirs, which is not, however, 

 independent of that of the air, but has probably a fixed relation, and is controlled by it. 

 The temperature of a place, if derived from observations taken just beneath the surface, 

 would be foinid to vary in its mean several degrees. 



The climate of the soil has not, so far as we have observed, been determined for any 

 latitude : indeed we do not know that any observations have been made upon the subject. 

 We shall here give a few observations of our own ; they may be regarded as a beginning 

 of an inquiry, which may result in something at least interesting if not useful. There are 

 certain conditions of the soil, which modify its temperature, irrespective of place or height. 

 The principal modifying condition is water. The influence of this is well known, and the 

 popular opinion here is correct : wet lands are said to be cold ; tlie application of the thermo- 

 meter proves it, and this coldness is found to arise from a superabundance of water. The 

 coldness in question depends upon the property of evaporation : water, in passing from a 

 liquid form to that of vapor, takes caloric from the surrounding bodies ; and hence where 

 this process goes on rapidly, the surface will be kept cold by the loss of heat required to 

 convert a liquid into a vapor. 



The following observations were made in this city, upon soil which is always slightly 

 shaded, or which never receives the direct rays of the sun. The bulb of the thermometer 

 was usually placed about seven inches below the surface. The place for inserting it was 



