THE OLD RED SANDSTONE. 183 
vis, and through the exquisitely pastoral valley of Strathpef- 
fer. The higher hills which rise over the valley are formed 
mostly of the great conglomerate — Knockferril, with its vit- 
rified fort—the wooded and precipitous ridge over Brahan 
—and the middle eminences of the gigantic mountain on the 
north; but the bottom and the lower slopes of the valley are 
occupied by the bituminous and sulphureous schists of the 
fish-bed, and in these, largely impregnated with the peculiar 
ingredients of the formation, the famous medicinal springs of 
the Strath have their rise. They contain, as shown by chem- 
ical analysis, the sulphates of soda, of lime, of magnesia, 
common salt, and, above all, sulphuretted hydrogen gas— 
elements which masses of sea-mud, charged with animal 
matter, would yield as readily to the chemist as the medicinal 
springs of Strathpetfer. Is it not a curious reflection, that 
the commercial greatness of Britain, in the present day, should 
be closely connected with the towering and thickly spread 
forests of arboraceous ferns and gigantic reeds — vegetables 
of strange form and uncouth names— which flourished and 
decayed on its surface, age after age, during the vastly ex- 
tended term of the carboniferous period, ere the mountains 
were yet upheaved, and when there was as yet no man to till 
the ground? Is it not a reflection equally curious, that the 
invalids of the present summer should be drinking health, 
amid the recesses of Strathpeffer, from the still more ancient 
mineral and animal debris of the lower ocean of the Old Red 
Sandstone, strangely elaborated for vast but unreckoned peri- 
ods in the bowels of the earth? The fact may remind us of 
one of the specifics of a now obsolete school of medicine, 
which flourished in this country about two centuries ago, and 
which included in its materia medica portions of the human 
frame. Among these was the flesh of Egyptian mummies, 
