Found on the Francis A. Countway Library of Medicine website. Warren Anatomical Museum: 21595.  Experimental human body plethysmograph manufactured by JH Emerson Co.  Machine was used to measure lung capacity. A person would sit inside the box with his head in the glass dome on top and breathe into the tube on front of dome. Machine is wooden and “L” shaped, designed to fit around a seated human, and latches closed. A spirometer would have rested on wooden edge. Two thermometers affixed to front measured interior and exterior temperatures. Tubing, gauge, and motor are affixed to right side. Rear of machine has attached wires and area marked “Sears-port”.  83 D x 59 W x 152 H cm.