DAMP AIR OF Bey SPOTS. 175 
been known to extend itself exclusively to habita- 
tions situate in the course of a river or on the banks 
leading to it. The notator to Carrington’s “ Dart- 
moor” who does not allude to the cause of this 
fever, nevertheless confirms the above idea in a 
marked manner in the following passage. “ The air 
“of Dartmoor being healthful and bracing, its 
“inhabitants commonly called moorsmen, as a 
“‘ natural consequence are famed for strength and 
“longevity, as well as for considerable skill in the 
“ art of wrestling, although occasionally in the deeper 
“vallies Typhus fever has prevailed.” That so 
formidable a disease should obtain in the immediate 
vicinity of a district proverbially healthful, is a 
marked indication of the concomitance of this af- 
fection with depressed sites. It may however be 
exceeding the bounds of propriety to affect any 
precise knowledge of the cause of this formidable 
disease, and notwithstanding I have just intimated 
the probability of the insufficient stimulus to the 
nervous system and insufficient oxygenation of 
the vital fluid being the causes indirectly inducing 
it, it may be equally philosophical to regard the 
unfavorable influence of the atmosphere of our 
vallies on the due excretory function of the skin 
as productive both of Typhus fever and of the 
various descriptions of inflammatory attacks refer- 
red in ordinary parlance to that comprehensive 
term “‘colds.” To understand the absolute state 
of the air of low situations correctly, it is only ne- 
cessary to look down on some valley from an 
adjacent eminence on a cold day succeeding rain 
or fog. Directly the sun which while at his height 
had kept the exhalations in too subtle a form to be 
perceived, begins to sink towards the horizon and 
to withdraw his heat, the whole of this fine vapour 
assumes a condensed aspect, and will even at times 
take on the deceptive appearance of an estuary or 
