PLATE XXXI 
Fig. i.—Structural iron framework for respiration chamber: A, Sills and ceiling 
plates of angle iron; B, studding and joists of light weight channel iron, with narrow 
edge; C, asbestos building lumber to support copper floor; D, supports for exterior 
cover of cork board and museum board. 
Fig. 2.—Copper-walled chamber attached to inside of iron framework: A, Bolts for 
attaching wall to structure; B, wooden insulation between iron and copper; C, 
thimbles soldered to outside of copper wall to receive inner end of thermoelement 
described on page 331. 
