121 [Er 
veloped on these points; and yet we are notmuch 
enlightened by the investigation. All that seems 
to be clearly ascertained in relation to these re- 
medies, is, fortunately, what chiefly concerns us; 
their practical uses. —* 
Experience has funished ample knowledge on 
this point ; and we may, without any material 
interference with a just appreciation of their real 
eflicacy in various affections, leave the unsettled 
points of modus operandi, to the ingenious-dispu- 
tatious. But, that you may not be uninformed on 
the se End Ste of these varied and vascillating 
opinions, [ shall briefly enumerate the chief of 
them :— 
Cullen, in conformity with the key-note of his 
theory of fever, believed they relaxed spasm of 
the cuticular vessels: thus helping the cure by re- 
moving the cause, and consecutively inducing 
their well known diaphoretic effect; and -in spas- 
modic affections, performing the part of antispas- 
modies. Many of the older writers conceived | 
that much of their beneficial operation was attri-— 
butable to the serous evacuation they induce, while 
the skin is ina state of vesication. And as it has 
been sometimes observed that the establishment 
of puriform discharge gave the first indication of 
benefit, it has been surmised, that additionat 
strength was added by that fact, to the idea of 
their depleting quality. By some it has been sup- 
posed that blisters operate in removing local pain, 
by creating a new action in an outward part: thus 
abstrating the force of morbid excitement concen- 
trated within, and inviting it toa less injurious 
seat of action, leaving the internal diseased action 
by that much the weaker, and consequently in the 
way of a spedier return to equalized healthy action, 
This opinion embraces a wider range. It extends 
