268 Dr. Prout on the Phenomena of Sanguification, [APRit, 
into which this gas enters.* The changes produced upon the 
fluids or blood of these animals are unknown. As to the second 
consideration, whether different individuals of the same class 
differ in the degree of their respiratory powers, we have likewise 
no very good experiments ; and even those we have, from want 
of due attention bemg paid to circumstances which materially 
influence their results, and which will be considered more fully 
under the next head, can hardly, perhaps, be fairly compared 
with each other. In a paper which I published some time ago 
onrespiration, I collected the results of all the chief experiments 
on record, and arranged them in the following tabular form; 
* and although they do not show the exact degree in which indi- 
viduals differ from one another, they demonstrate beyond a 
doubt that such differences do exist.+ 
Cubic Inches. 
M. Jurine of Geneva “ imagined” that for every 
100 cubic inches of atmospheric air respired, 
there were given off of carbonic acid........ 10°00 
Goodwin estimated the quantity at .......... -- 10:00 or 11-0 
Menzies, from experiments made with considerable 
accuracy, at........ ee ot eee 5°00 or 5:1 
Lavoisier and Seguin appear to have made it much 
less, especially in their later experiments. From 
the data in my possession, I am unable to ascer- 
tain the precise proportion. 
Dr. Murray found it vary from...........-.... 620 to 
Sint. Davy, from... ov:suiees § Bas + Pewne febH .. 3°95 to 
Messrs. Allan and Pepys, from 3:50 to 9°50 pe 
cent. according as the first or last products of 
an expiration were tried. They estimated the 
mean at about...... e Cutieapeshhi: tke aegis: crete Badd 8:00 
Myself, from 4:1 to 3°3. Me 
MOOR ih sigh Aes aloha as. opines faisds iw nieloyely med See 
A friend, about ...... a ahi Wy ihe eines, seavtbioe thakd 4-60 
DoF yfe gh) ao pte is apeie Soyo Afters <hodlalin: 905) vie ashe ee ene 
Now it will be proper to observe, that it has been estimated 
that the lungs of an ordinary man contain about 280 cubic inches, 
one seventh of which, or 40 cubic inches, is drawn in and 
expelled at every inspiration and expiration, the number of which 
inspirations and expirations in one minute has been estimated at 
about 20.8 Hence, such a man will breathe about 28,800 times 
in 24 hours, and take into his lungs, during that period, 
1,152,000 cubic inches of atmospherie air; and says Berzelius, 
wD 
nH 
* Annales de Chimie, vol. xii. p. 273. 
+ See Annals of Philosophy, vol, ii. p. 333. 
t See Disser‘atio inauguralis de copia acidi carbonici e pulmonibus inter respi- 
randum evoluti, p. 11. : R 
§ See Bostock on Respiration. Also Thomson’s Chemistry, vol. y. article 
Respiration. 
