ON THE ACTION OF DIURETICS. 
643 
kind of nervous refrigeration of which we have been speaking ? 
Yes or no? Yes! whenever the cooling of the skin is owing to 
any external cause, or to the use of drinks which counteract pul- 
monary combustion. No ! whenever the diminution of the super- 
ficial heat of the body is owing to a narcotic action or to a sedation 
of the centres of organic life. In fact, do we not observe, as the 
result of all narcotic and other empoisonments, a profound sedation, 
a considerable lowering of the temperature of the skin, with abund- 
ance of cold perspiration, and, nevertheless, often with copious uri- 
nary emissions? 
Thus, we admit that diminution of the temperature of the skin, 
diminution of its vitality, can, independently of the cessation of its 
secretory functions, produce a more or less copious diuresis, by a 
sort of nervous refrigeration or sympathetic action. 
2dly. Chemists are able on this interesting question to furnish 
us with valuable information, inasmuch as they have discovered 
and demonstrated the activity of organic combustion or respiration 
to be in inverse ratio to that of the depurative secretion of urine. 
Through respiration are combusted and eliminated, under the form 
of carbonic acid and water, the carbon and hydrogen of the aliments ; 
and through the kidneys, under the form of urea, uric acid, and 
hippuric acid, the azote of the alimentary matters. Now if, from 
any cause, respiratory activity diminishes, as under the influence 
of sedative and narcotic medicines, the carbon and hydrogen of the 
aliments are expelled by the kidneys in a more complex form, 
particularly in that of uric acid, uro-benzoic acid, more carbonized 
and hydrogenated than urea, from the oxygen of the inspired 
air not being sufficient to generate more simple compositions, such 
as carbonic acid and water. 
In accordance with these principles, it may happen also, that, 
under the sedative influence of the diuretics now occupying us, 
the respiratory and cutaneous functions charged with the elimina- 
tion of carbonic acid and water (the products of organic combustion), 
diminished in their activity, might have their place supplied in 
this depuratory function by the kidneys: whence arises acceleration 
of their secretory action and the consequent development of di- 
uresis. 
From the preceding considerations, taken collectively, it follows 
that sedative diuretics are medicines of great power ; — that they are 
capable of deeply altering the economy, whether it be through the 
mutation of the matters of nutrition, or through the nervous acti- 
vity which regulates the great organic functions ; therefore it be- 
comes our duty to use them with prudence, and never to lose sight 
of their depressive effect on the nervous system. The cases they 
are best suited for are the phlegmasise, in which predominate 
