IN DISEASES. 377 



tion employed, as was done by Regnault and Reiset, and in part 

 also by Bidder and Schmidt. In these experiments, as in most 

 cases in which animals were experimented upon, the whole amount 

 of the perspiration was determined by inclosing the animals in a 

 receiver to which fresh air was conveyed, while the air already used 

 was carried off by a system of vessels for the purpose of being 

 absorbed. I have myself* made experiments of this kind on the 

 process of inflammation. The most important obstacle to such 

 inquiries in the case of animals, is that many diseases which are of 

 the greatest importance in the eyes of the physician, cannot be pro- 

 duced by operations, or any other artificial means. There are very 

 few places, moreover, in which the experimentalist has the oppor- 

 tunity of carrying on a series of investigations on spontaneously 

 diseased animals. On this account, the human subject has hitherto 

 been most frequently experimented upon, for the sake of investigat- 

 ing the process of respiration and its effects on the excretion of 

 carbonic acid in disease. Hannoverf has partially co-operated with 

 Scharling in employing the last-named method for determining 

 simultaneously the pulmonary and the cutaneous perspiration. 

 This method is undoubtedly the best adapted for examining the 

 respiration during disease, provided the patients can, without any 

 inhuman aggravation of their condition, bear to be moved and tem- 

 porarily confined within a closed receiver. It cannot be denied 

 that even in this mode of experiment, the true effect of disease 

 upon the exhalation of gas is unavoidably modified, at least during 

 an experiment of short duration, by the mental excitement of the 

 patient ; but this evil is far less completely rectified in Prout's 

 method, which has been followed by Malcolm,! Hervier and 

 St. Sager, and Doyere.|| It demands considerable practice to 

 acquire the facility exhibited by Vierordt, in breathing with perfect 

 calmness into an apparatus, however well it may be constructed; 

 the disease may often run its course before the patient is able to 

 acquire the necessary proficiency, while on the other hand humanity 

 forbids us to torture a fever-patient for any length of time with 

 such experiments. Hence great caution should be exercised in 

 deducing scientific conclusions from any observations of this 

 kind. Then, moreover, in the experiments made according to the 



* Abhandl. d. Begrund. d. k. sachs. Ges. der Wiss. 1846, S. 465. 

 t De quantitate acidi carbonic! ab horaine sano et segroto exhalati. Havnise, 

 1845. 



J Monthly Jotirn. of Med. Science. January, 1843. 



Compt. rend. T. 28, p. 260 ; Gaz. des Hospitaux. 1849, p. 85. 



II Compt. rend. T. 28, p. 636. 



