8o 



The Estimation of Nitrogen 



[113, 114 



for temperature and pressure, as the two operations were con- 

 ducted under as nearly as possible the same conditions. 



113. Lunge's Nitrometer Method.— Lunge's nitro- 

 meter was originally invented to estimate the amount of nitrogen 

 in ' nitrous vitriol.' Two modern forms of the apparatus are 

 shown in figs. 33 and 34, the only difference between the 

 two forms being their capacity. In 

 fig. 33 a is a calibrated tube con- 

 nected above with a three-way 

 tap, d, and below with a piece of 

 stout-walled india-rubber tubing c. 

 The tube b is not calibrated. / is 



Fig. 33. 



Fig. 34. 



a funnel by means of which liquids may be introduced into 

 a, and e is a thick-walled tube of small bore by means of which 

 gases may be introduced or drawn off. In fig. 34 the same 

 parts are shown, but two large bulbs are blown in the tubes, so 

 that the amount of gas which may be experimented with is 

 greatly increased. 



114. The Estimation. — Fill the apparatus with the bulbs 

 (fig. 34) with mercury as shown in fig. 33, and turn the tap so that 



