1919] 



ALLEN AND DAVISSON — NITROGEN APPARATUS 47 



line solutions. The surface of the bulb is large enough to 

 provide sufficient condensation to form a water trap, through 

 which fixed alkali will not pass. This point was tested by an 

 experiment in which conditions were also purposely extreme. 

 There were placed 100 cc. of concentrated alkali and 100 cc. 

 of nitrogen-free water in the distilling flask and zinc added, 

 just as in the case of the regular nitrogen determinations. 

 The distillate was collected in three portions of about 80 cc. 

 each, and in no fraction was there sufficient alkali to be de- 

 tected with N/100 acid. 



The requirements as to quality of joint at D are not so 

 exacting as in the case of joints for ether extraction and 

 similar apparatus, for the reason that a safe connection may 

 be made with the aid of a water seal, using a joint less close- 

 fitting than might otherwise oe demanded. For this reason 

 we hope the manufacturer will eventually be able to make the 

 flasks interchangeable on diff € rent pieces of apparatus. This 

 point is under consideration at the present time. 



