794 DIGGING AND PREPARATION OF PEAT. 



Thus fens and morasses may contain patches of high peat-bog, 

 and frequently pass completely into the latter form, as in 

 many North German districts. 



Besides the above-mentioned kinds of bog, there are seaside- 

 bogs and forest-bogs. The former are found on lowlands 

 along the seaside, which either are inundated occasionally by 

 the sea, or into which brackish water infiltrates, or are 

 caused by the damming of the mouths of rivers or small 

 water- courses by the tides. Forest bogs are those in which a 

 great number of trunks of trees in more or less good preserva- 

 tion (bog-oak, etc.) are imbedded. These trees are sometimes 

 erect, as in the Wicklow mountains, and sometimes lying 

 horizontal, as at Sunningdale, in Berkshire. Both these 

 forms of bog, however, come under one of the headings 

 already mentioned. 



The peat found in the different bogs varies greatly in its 

 character, according to the degree of decomposition it has 

 undergone, its greater or lesser contents of humic acid and 

 carbon, the vegetable debris of which it is composed, and 

 finally the comparative quantity of earthy material which is 

 mixed with it. Some peat resembles lignite both in appear- 

 ance and economic value, whilst other kinds hardly can be 

 distinguished from slightly decomposed vegetable remains. 

 So many bogs are intermediate to these extreme forms, that it 

 is difficult to characterise even a few of them. They are 

 distinguished frequently by means of the plants from which 

 they are formed, such as heather-peat, moss-peat, wood-peat, 

 sedge-peat, etc., but thus no true standard of quality can be 

 obtained, as each variety may represent peat of every 

 possible quality. The best way to judge of the latter is to 

 consider the degree of decomposition of the vegetable debris, 

 the degree of cohesiveness of the particles of peat and their 

 density. In this way, the following kinds of peat may be 

 distinguished : 



(a) Amorphous or Black peat, a dark brown or blackish 

 peat with silky lustre on a clean-cut section, heavy, generally 

 rich in carbon, when dry, breaking with a eonchoidal fracture. 

 This peat is found generally in the deeper strata of a bog, and 

 the plants of which it is formed are scarcely recognisable. 



