130 NORTH UIST. PEAT. 



into peat is very obvious, and the consequent increase of 

 that substance is easily understood, without endowing it, 

 as has been often done, with living powers. It is most 

 easily seen in the Sphagnum. In this, as the lower ex- 

 tremity of the plant dies and is decomposed, the upper 

 sends forth fresh roots, like most of the mosses ; the 

 individual thus becoming in a manner immortal and sup- 

 plying a perpetual fund of decomposing vegetable matter. 

 A similar process, although less distinct, takes place in 

 many of the rushes and grasses; the ancient roots dying 

 together with the outer leaves, while an annual renovation 

 of both perpetuates the existence of the plant. Other 

 vegetables again add to the common stock by their annual 

 death, their existence being repeated in seedling plants ; 

 while others still, of a perennial nature, contribute only 

 by the ordinary decay and renewal of their leaves and 

 flowers. 



The progress of this decay, the gradation from the 

 living vegetable to solid inorganic peat, is generally easy to 

 trace. Where the living plant is still in contact with it, 

 the roots of the rushes and ligneous vegetables are found 

 vacillating between life and death in a spongy half decom- 

 posed mass. Lower down, the pulverized carbonaceous 

 matter is seen mixed with similar fibres still resisting 

 decomposition. These gradually disappear, and at length 

 a finely powdered substance alone is found, the process 

 being completed by the total destruction of all the 

 organized bodies. If this process has been carried on 

 upon a drained declivity, the result is a loose powdery 

 matter, namely, heath soil, or mountain peat ; if in an 

 inundated or wet soil, it is a mixture of that powder in the 

 water, or the flow moss of agriculturists. Intermediate 

 circumstances produce intermediate conditions, and thus 

 many varieties of peat are the result ; while all these are 

 further increased by differences in the vegetable ingre- 

 dients, in the time during which the process has lasted, 

 in the degree of drainage, and in the elevation or other 



