490 PREHISTORIC EUROPE. 



tion in Scotland. The country people would be very well pleased 

 if peat available for fuel would form in places which were 

 stripped bare by their fathers and grandfathers. But they know 

 that with every year that passes fuel must be sought for farther 

 and farther afield, and I have frequently seen it brought from 

 distances of several miles to hamlets and villages in the imme- 

 diate neighbourhood of which it used to be dug 50, 100, or 150 

 years ago, but where there is not the slightest evidence of any 

 appreciable peat-growth having taken place since the bogs were 

 exhausted. If the present rate of growth in such regions were 

 to be taken as a standard of comparison, what age should we 

 assign to bogs exceeding 20 or 30 feet in depth ? It would be 

 absurd, however, to suppose that peat has never grown more 

 rapidly in former times ; and the occurrence of Eoman and 

 Scoto-Saxon relics embedded in the bogs is proof that even in 

 the historical period the rate of growth has exceeded that which 

 we now observe in Scotland. But it is not always safe to infer that 

 all the peat that overlies a Eoman sword or axe has been formed 

 since the Boman occupation. Metallic objects might easily sink 

 in time through a considerable depth of soft peat, and I know 

 that a geological hammer of no great antiquity might be disin- 

 terred to-morrow from a quaking bog in South Ayrshire, probably 

 at a depth of several feet from the surface. Peat is not now 

 increasing generally in Scotland — the rate of decay is in excess 

 of growth in most bogs which I have visited, and Blytt has made 

 the same observation in Norway. Here and there, however, 

 when the supply of moisture is abundant, the bog-mosses thrive 

 well enough, and are doubtless adding to the thickness of the 

 peat. But I can give no measurements to show the average 

 rate of growth in such places. Mr. Kinahan states that in cer- 

 tain Irish bogs " each year's growth is represented by a layer or 

 lamina, and these laminae in the white turf (uppermost portion 

 of a bog) are about, on an average, one hundred to the foot ; in 

 brown turf (lower portion) two hundred to three hundred ; and 

 in black turf (bottom portion) from six hundred to eight hun- 

 dred ; but their numbers are different in . the different bogs, as 



