X.EXPEC 
the exhalants can 
of producing it by some specific action on the parts concerned, there 
‘seems no reason to believe in the existence of such remedies. . - iad 
r. Cullen supposed that expectorants might act by promoting the — 
ation of a thin fluid, which diluting the viscid mucus present — 
mucus follicles in the lungs and windpipe, might facilitate its. 
ection. But the action of the different individuals belonging to” 
the class, and especially their effects in various diseases, cannot be 
; _ explained on this principle. = ae ; 5 ae 
: There are probably various modes of operation by which certain — 
remedies will appear to promote expectoration, and which will gi 
them aclaim to the title of ex pectorants. Ve 
' Thus, in certain diseases the exhalant vessels.in the lungs, seem 
_ to be in that state, by which the exhalation of fluid is lessened, or 
~ nearly stopped, and in such cases expectoration must be diminished 
Any medicine capable of removing that constricted state, will ap pear 
to promote expectoration, and will at least relieve some of the 
of the disease. It is apparently by such a mode of ope 
at antimony, ipecacuan, squill, and some others, pr 4 
expectoration in pneumonia, catarrh, and asthma, the principal dis- 
eases in which expectorants are employed. 2 eee 
_ There is acase of an opposite kind, that in-which there is a r 
_ dundancy of mucus in the lungs, as occurs in humoral asthm 
these affections, certain expectorants are supposed to prove” 
If they do so, it is probably by being determined more. pa 
in their action to the pulmonary vessels, and by their 2 
stimulus diminishing the secretion, or increasing the  uiisa 
lessening the quantity of fluid, and thereby rendering the expectora- 
tion of the remainder more easy. The determination of these : 
stances to the lungs is often perceptible by their odour in the air eX 
‘pired. A similar diminution of fluid in the lungs may be effected 
es 
_by determining to the surface of the body, and those expecto 
which belong to the class of diaphoretics probably act in this 
ner. — - 
, a then, are to be regarded, not as medicines 
directly assist the rejection of a fluid already secreted, but rather 
either increasing the natural exhalation where it is of: 
diminishing the quantity of fluid where jt is too copious, ¢ 
stimulating the pulmonary vessels, or by determining to’ 
_4n both cases expectoration will appear to be promoted or f ee 
