METHODS OF HARVESTING. 795 



(b) Fibrous or Brown peat, of a loose fungoidal structure, 

 in which the component plants, grass, moss, heather, reeds, 

 sedge, etc., are generally recognisable ; it is usually of a lighter 

 colour than black peat (yellowish to dark brown), less heavy, 

 more or less carbonaceous, when dry does not crumble and 

 usually occurs in the upper strata of a bog. 



(c) Dredged peat, a more or less tenaceous black peaty mud, 

 forming the lowest layer in morasses, showing no visible 

 vegetable structure ; when dry, it has a peculiar lustre and is 

 heavy; owing to its muddy character it generally is moulded 

 into various shapes. 



Between dredged and black peat (the best kinds) and brown 

 peat, there are numerous intermediate varieties, the quality of 

 which is considerably modified by the amount of earthy admix- 

 ture they contain. This earthy matter consists partly of the 

 ash-constituents of the peat-forming plants, and partly is 

 introduced accidentally by inundations, etc. 



SECTION III. METHODS OF HARVESTING PEAT. 



Before undertaking to work a peat-bog, a full estimate 

 should be prepared of its quality and its probable volume, in 

 order to determine whether the outlay of capital expended in 

 removing the peat will be covered by its value and that of the 

 cleared land. 



1. (JiKiiitit)/ of Peat. 



The following data are required to estimate the quantity of 

 peat in a bog : the area, depth, amount of shrinkage of the 

 dried peat and the loss of peat during its extraction. 



(a) The area of a bog should be ascertained by surveying it. 



(b) The depth may vary considerably at different points of 

 a bog, which is not unfrequently intersected with one or more 

 layers of sand, loam or trunks of trees. In order to become 

 acquainted with the nature of the bog, it should be divided 

 into a rectangular network, the points of intersection of which 

 may be about 27 yards (25 meters) apart, and are marked by 

 numbered stakes. Three methods can then be followed; either 

 strong poles are driven down at each numbered point to the 



