276 WHERE PEAT IS TO BE EXPECTED. 



while its limit towards the poles appears to be within the 60th degree. 

 It is a product, therefore, chiefly of the temperate regions. 



Still, on the equator itself, at a sufficient altitude above the sea, the 

 temperature may be cool enough to pennit the growth of peat. Hence, 

 though on the plains of Italy no peat is formed, yet, on the higher Ap- 

 penines, it maybe here and there met with, among the marshy basins, 

 and on the undrained mountain sides. 



2°. The occurrence of stagnant water is necessary for the production 

 of peat. Hence, on impervious beds of clay, through which the rains 

 and springs can find no outlet, the formation of peat may be expected. 

 Thus on the Oxford clay repose the fens of Lincoln, Cambridge and 

 Huntingdon (p. 245). On impervious rocks also, peat bogs form for a 

 similar reason. The new-red sand-stone is occasionally thus impervi- 

 ous, and on it, among other examples, repose the Chat moss, the tract of 

 peat, mostly in cultivation, which lies west of a line drawn between 

 Liverpool and Preston, and the large extent of boggy country which 

 stretches round the head of the Solway Firth. On the old red sand- 

 stone, the mountain lime-stone, the slate, and the granite rocks, much 

 peat occurs, and it is on these latter formations that the extensive bogs of 

 Scotland and Ireland chiefly rest. 



But though these two facts are of some value to the politician and to 

 the geologist in indicating in what countries and on what formations peat 

 may be expected to occur, yet they are of comparatively little impor- 

 tance to the practical agriculturist. It is of far more consequence to 

 him that the moment he casts his eye upon the face of a country he can 

 detect the presence or absence of peat — that none of the perplexities 

 which beset the nature and origin of other superficial accumulations at- 

 tach to this — that he can, at once, judge both of its source and of its agri- 

 cultural capabilities. Though produced on a given spot, because rocks 

 of a certain character exist there, yet its origin is always the same — its 

 qualities more or less uniform, — the improvement of which is susceptible 

 in some measure alike, — and the steps by which that improvement is to 

 be effected, liable to variation, chiefly according as this or that amelio- 

 rating substance can be most readily obtained. 



