. 
C. W. Hinman —New Apparatus for Gas Analysis. 188 
uring tube can thus be kept pragig oh? its well: or g can be 
The mercurial trough is of cast iron, and consists 0 
which is about 130 mm. square, 15 mm. thick, and has a groove 
mm., bent so that when it is put into the side well m, the point 
sega pee ean be brought directly under the measuring 
tube, 
a of metal ¢, which ‘a tetened into the upper disc 7. 
of the tripod are screwed into a dise 7. This style of 
* e method of avoiding observations of 
nena honor nn net Ae IL, xlix, 376, 1869.—Eps. 
