722 DIGGING AND rREPARATION OF PEAT. 



humus, liesidos iutcrruptin*^ the natural drainage, frequently 

 cause the formation of a peat-bog. 



(4) The porosity of the soil. When the sub- soil consists of 

 permeable sand or gravel (as in the case of several Dutch and 

 North Cicrman bogs) the situation being low either on a level 

 with a lake or slightly elevated above it, the soil is maintained 

 constantly wet by the subsoil water. 



(5) Inundations, when repeated annually and lasting for some 

 time. 



(G) Finally, peat-bogs once established cause water to 

 accumulate and may gradually extend over adjoining land. 



[Some European peat-bogs are of great age and contain remains of 

 extinct animals (Irish elk, ifec.) and of arctic flora, dating from the 

 close of the Glacial Period. — Tr.] 



Section II. — Different kinds of Bogs. 



Peat-bogs vary considerably in appearance, being composed of 

 different plants, and containing ditierent kinds of peat. Thus, 

 in North Germany, high peat-bogs {llnch-moore), are distin- 

 guished from fens {Gr'unlamhmoorc, or JiriicJicr) ; in South 

 Germany, there are high peat-bogs and morasses {Wi<'se7imoon'), 

 while Lesquereux classifies Swiss bogs as super-aquatic and 

 infra- aquatic, corresponding to high peat-bogs and swamps. 



]. llifjli Pcat-hofis. 



High peat-bogs termed also peat-mosses, peat-moors or wolds 

 are chiefly characterised by the prevalence of peat-moss 

 (Sphagnum), and a dense growth of heath plants {CaUiiiia, 

 Erica, Andromeda and Vaccinium) ; in South Germany, also, 

 the mountain-pine (Pinus montana) appears on these bogs. 

 These i)lants grow gregariously on extensive areas and form most 

 of the peat. Such bogs are characterised by a gravelly or 

 clayey subsoil and by the convex arched shape of their 

 surface. 



Whilst the South German bogs owe their origin to a more oi- 

 less clayey subsoil, in North Germany the latter is more per- 

 meable and water constantly permeates the bogs from the 



