NORMAL PROCESSES OF ENERGY METABOLISM 541 



the burette are given in Boothby and Sandiford's book on "Basal Metabolic 

 Rate Determinations." 



Fig. 19-a. Henderson modification of Haldane apparatus (Bailey). (1) Burette 

 graduated in hundredths of a c.c.; (2) four-way stop coek at top of burette; (3) con- 

 trol tube same volume as burette; (4 and 5) glass tubes for circulation of air through 

 water jacket; (6) mercury reservoir for varying pressure in control tube; (9) mer- 

 cury reservoir for filling and emptying burette; (10 and 11) cord and counter-weight 

 for suspending mercury reservoir; (12> potash pipette; (13, 14, 15) tubing and 

 leveling bulb for potash pipette; (16) pyrogallol pipette; (17) leveling on pyrogallol 

 pipette; (18 and 19) leveling marks on potash pipette; (20) connection to sampling 

 bottle. 



e. Analysis of Outdoor Air. Haldane working with the portable 

 form of his apparatus found that outside air contains 0.03 per cent of 

 carbon dioxid and 20.03 per cent of oxygen. Benedict using the Sonden 

 apparatus found as the result of 212 analyses in the Back Bay district 



