PHYSICAL AND LITERARY. 237 



when a flrong heat is wanted j and even in 

 common peats, I have fhewn you how far 

 preferable the hard and folid are to the light 

 and fpiingy. By fome experiments which I 

 have made, I find it to be no difficult mat- 

 ter, to bring peat to a confiderable degreq 

 of folidity, as you yourfclves may fee by the 

 fpecimen I now iTiow you. The fimple o- 

 peration of grinding, does the buiinefs ; and 

 as a peat, when taken out of the mofs, is a 

 foft body, and eafily grinded, a machine may 

 be eafily contrived to grind, at a moderate eXf 

 pence, feveral tuns in a day. The charge 

 of digging peats, cutting them into fquares or 

 the form of bricks, when of a proper dry- 

 nefs, will be little different from that of ma- 

 king peats in the ordinary way. The foli- 

 dity of peat prepared in the manner menti- 

 oned is furprifing ; its fpecific gravity being 

 fomewhat greater than that of pit-coal. I 

 compared a peat of this kind with a piece of 

 coal brought from Baron Clerk's coal-mines 

 near Edinburgh, and by the hydroftatical ba- 

 lance, reckoning water 1000, their fpecific 

 gravities were nearly as follows, pit-coal 

 1287, folid peat 1303. 



Fro?4 



