156 BOARD OF AGRICULTURE. 



Continuing- his notice of the geology of this locality, Dr. Jackson 

 makes some remarks so interesting, that, notwithstanding their 

 length, I am tempted to introduce them at this place. He writes : 

 " No fossiliferous rock of t|ie kind occurs in the area between this 

 locality and the spots where are found the diluvial boulders noticed; 

 the marks on the surface of the ledges, have long ago indicated to 

 me that the parent bed of these fossils was to be sought inland, 

 farther to the north than where they are found loose in the soil. 

 "We consider this discovery of the most conclusive kind, and one 

 of great importance in the theory of diluvial transportation, both 

 of minerals and soils. By knowing the directions from whence 

 the scattered fragments came, we can trace rocks and minerals to 

 their native beds, and we can predict and account for the distribu- 

 tion and qualities of soils, which would be wholly obscure without 

 the above considerations. Thus, since all the diluvial soils have 

 been moved southwardly, it is evident that the soil from one rock 

 overlaps that of another, and so far as I have observed, the soils 

 resting on a rock are rarely derived from its decomposition, but 

 from those to the north. This rule indicates their treatment, for 

 their mineral ingredients denote the amendments required. Thus 

 persons who believed the soils of Thomaston to be the result of the 

 decomposition of the rocks immediately below, would be apt to 

 think that they must contain much lime, but they do not, and orig- 

 inated from granitic and mica slate diluvium — and experience, since 

 we have urged the trial, demonstrates that the soil of that town 

 needs liming to a great extent. Ilundreds of other instances of 

 this kind I have recorded, but let this suffice for the present." 



At the Forks of the Kennebec river, the rocks are found to con- 

 sist of argillaceous and calcifcrous slate, with numerous beds of 

 fine grained graywacke. In Solon, enormous blocks of mica slate, 

 containing staurotides and mucles occur. The rocks in New Port- 

 land arc strongly charged with pyrites, which is magnetic, and 

 causes a powerful deflection of the magnetic needle. 



Beds of clay are found in various parts of the county, and brick- 

 making is carried on to a limited extent in most of the towns. 

 There being but little foreign demand, and but a small home con- 

 sumption, the business is confind to a local sphere, each town 

 manufacturing enough to supply its own market, 



A ledge of rocks, containing a large proportion of carbonate of 

 lime and green calciferous slate, occurs near the Forks of the Ken- 

 nebec, whicli, on account of the fineness of the grit, has been 



