A SERVICEABLE FORM OF CAPILLARY ELECTROMETER.
C. C. GUTHRIE, S.B., M.D.(From the Hull Physiological Laboratory, University of Chicago.)CHICAGO.I have been using the capillary electrometer, figured below, for some time, and it has proved so satisfactory that I consider it worthy of a brief description. I ordinarily work with the capillary tube horizontal and the description will be of it in that position.Figure 1 shows the appearance of the capillary and cup when viewed from above. A is a glass tube drawn into a capillary and fused into the acid cup B at X. The superior and inferior surfaces of the cup B are flat and parallel. Each surface is dilated into a small reservoir C and E (see Fig. 2). C has a hole in the top which is sealed with acid-proof wax after the cup is filled with acid, care being taken that a large