354 



RESPIRATION. 



which was exhaled with the carbonic acid was almost precisely 

 the same as in the former case, namely 100 : 75*3. There were 

 95'7 grammes of aqueous vapour exhaled for 100 parts of carbonic 

 acid; only 21'95^ of the excreted water was eliminated by the 

 skin and lungs. Whilst, however, in the first case, where no 

 ingestion of water vAas allowed during inanition, there were daily 

 exhaled on an average 21*641 grammes of carbonic acid for 

 1000 grammes' weight of the animal, and 16-281 grammes of 

 aqueous vapour; while in the latter case, where water was freely 

 given, 16*30 grammes of carbonic acid and 15*60 grammes of 

 aqueous vapour were yielded by 1000 grammes' weight of the 

 animal; the loss was therefore far less considerable when water 

 was allowed than when both fluid and solid food were simul- 

 taneously withheld. 



The omission of even a single meal alters the relations of the 

 respiration very considerably, as is clearly shown by Vierordt's 

 observations on the influence of digestion. This observer, who 

 was accustomed to dine at half-past twelve, noted the following 

 relations in his own person, which show that the principal meal 

 exerts an influence in this respect which we could scarcely have 

 anticipated. 



We may see from this table that the individual respiratory 

 functions constantly diminish in activity after the last meal (or in 

 fasting), and that the ingestion of food very rapidly induces a 

 very considerable increase in their intensity ; the volume of each 

 inspiration is, however, diminished in the latter case, as we may 

 readily comprehend from anatomico-mechanical relations. Vierordt 

 has, moreover, convinced himself that there is a similar augmenta- 

 tion in the excretion of carbonic acid whenever dinner is partaken 



* The relative being of more importance in this table than the absolute 

 values, we have not deemed it necessary to reduce the cubic centimetres to 

 inches. G. E. D.] 



