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of fossilised trees much prized as a suitable substance for fancy 

 furniture and knick-knacks have given rise to the industry con- 

 nected with "bog oak." The districts of bogs are liable to 

 slipping and to settlement, and occasionally the wet spongy 

 ground on the slopes of the hills slides down bodily and destroys 

 the fields and property below. Another feature of peaty scenery 

 is the phenomenon known as " floating islands." There exist 

 many in shallow lakes and sluggish rivers. They consist of 

 masses of interlaced roots of plants, detached from the banks and 

 float down the stream. Oftentimes they are compact enough to 

 form soil, in which trees and plants grow, and on the Nile, 

 Ganges, and other great rivers constitute what is known as 

 " sudd." Perhaps the most singular and noted within our own 

 borders is that at Derwentwater. They appear periodically to 

 submerge and then emerge. The generation of gases produced 

 in waterlogged vegetation apparently supplies the intermittent 

 buoyancy and consequent fluctuations of level. In many parts of 

 the world floating islands have been utilised for the production of 

 such plants as cucumbers and melons. 



The diamond is another natural form of carbon, and a few 

 words must not be omitted from a geographical study. Although 

 its importance is nothing like that of coal, in many minor ways the 

 diamond has added its quota to the advancement of geographical 

 discovery. New tracts of the globe have been opened up solely 

 as the result of the discovery of the precious stone. Its rarity is 

 responsible for its price and not its applicability to arts and crafts. 

 Africa, particularly the Kimberley district, was almost entirely 

 opened up as a result of diamond mining. Brazil has derived 

 advantages for a similar reason. India, too, was very early noted 

 for the precious stone, but owing to the ancient nature of the 

 country and its tribes, coupled with their strife and contentions in 

 conjunction with their extravagant use of the rarity the store of 

 diamonds is now very small. 



The principal source to-day is the Capt, but the control of 

 the diggings is so carefully guarded that the output is not allowed 

 to exceed the demand. This preserves the output of the diggings 

 and maintains an almost uniform price. The diamond was re- 

 sponsible for at least one important commercial route. When 

 boring the Genai Tunnel rocks were encountered in the interior 

 which were so hard as to defy the entry of a drill for blasting 

 holes. The diamond drill was discovered to enable the work to 

 proceed, and the job was finished. The diamond has been used 

 throughout the world on similar occasions and on very similar 

 aims. 



Graphite, an allotropic form of carbon, is found naturally, 

 and is the substance perhaps best known in the cosmopolitan 

 article, the lead pencil. Its application in the arts and crafts are 

 numerous, and hence it is in great demand, and in commerce is 

 an important article. The great source of our own graphite was 

 the famous mine at Borrowdale, in (Cumberland, and pencil works 



