S3* 



On the Quantity of Carbonic Acid Gas [Nov. 



EXPER. I. 



Aug. 14, 1813.— Bar. 2994, Ther. 63. 



OBSERVATIONS. 



Before walk. 



After a short ditto. 



Example of oscillation alluded to p. 



note. 

 Return to standard. 



331, 



EXPER. II. 



—Bar. 29-9, Ther. 64. 



Before walk. 

 After a short ditto. 



> Example of oscillation above-mentioned 



Return to standard. 



7 65 



8 45 



9 30 



3-35 

 3-30 



3-30 



EXPER. III. 



Aug. 17.— Bar. 29-89, Ther. 64. 



340 

 3-30 



3-30 



70 

 68 



64 



Before walk. 



Five minutes after a very short and slow ditto: 

 This shows that moderate exercise scarcely 

 affects the quantity. 



EXPER. IV. 



-Bar. 30-17, Ther. 62. 



(Immediately after a very quick walk of \ 

 \ hour : great heat, and profuse perspiratiou. 



> Example of oscillation above-mentioned. 



derstood as measures of the capability of the organs of respiration to form 

 carbonic acid at any time, and not a« measures of the quantity of it formed in 

 a given time. The experiments of Messrs. Allan and Pepys show, that how 

 frequently soever air is received into the lung-, it always returns charged with 

 nearly the same quantity of carbonic acid. Hence during exercise, &c. when 

 the circulation is quickened, respiration is so also, and a greater quartity of 

 carbonic acid is formed in a given time than when these functions are in their 

 natural state, though the quantity formed at a single inspiration may be less. 

 Were not the respiration quickened when the circulation is so, a great portion 

 of the blood would pass through the lungs without undergoing that change, so 

 essential to life, which there takes place." 



* Of course most of the numbers in this column are only the result of esti- 

 mation. They arc introduced merely to show what the quantity would havt 

 been according to the general law, had not the experiments been made. 



