158 C. M. Warren on a new process 
receive the combustion tube, and a tubulure in the top for a ther- 
mometer, One end of the air-bath is made to rest on the com- 
2. 
packed with pure asbes- 
tos ; between 5 and c— 
a space of about two 
inches,—being left va- 
cant, a plug of asbestos ne wes . 
is placed at c; the space between ¢c and d, 4 to 5 inches in sonia 
is filled with an intimate mixture of asbestos and brown oxy 
of copper; and, finally, a plug of asbestos is placed at d. 
