On Idiotism. 95 
ance with well known facts. The modifica- 
tion of cutaneous diseases in passing through 
a variety of habits; the abuse of spirituous 
liquors; want of cleanliness and ventila- 
tion in habitations ; scanty cloathing ; coarse 
food; and the drinking of cold water are 
evidently of too general a nature, to produce 
a particular and local effect. Heat of the 
climate and stagnation of the air, considered 
as causes by Saussure (a) are at variance with 
common observation, since these affections 
are frequently observed in situations exposed 
to cold, wind, and moisture. The disease 
is endemial among some tribes of the Stone 
and Cree Indians inhabiting the banks of the 
Saskatchawan river, where it was observed 
by Dr. Richardson (2) in his journey to the 
Polar sea; the country is open, desert, and 
extremely cold, it consists of ‘ one vast 
plain whose boundaries are imperfectly 
known, it extends along the south branch of 
the Messouri and Assenaboine rivers, being 
(a) Je crois done qu’il faut chercher la cause de cette maladie dans 
quelque modification qui soit exelusivement propre aux vallées peu 
élevées au dessus du niveau dela mer. Or, je ne vois rien qui satisfasse 
Acette condition, sice n’est la chaleur et la stagnationde Vair renfer- 
mé par les montagnes qui entourent ces vallées. 
Saussure. Chap. 48, § 1035. 
(b) See A Journey to the Shores of the Polar Sea, &c. by Captain 
John Franklin, 4to. 1823. p. 116. 118, 119. 
