494 BELL SYSTEM TECHNICAL JOURNAL 



this manner was continued almost to the constricted portion. When 

 the capillary, after cooling, was examined under the microscope 

 minute globules of condensed mercury were plainly \isible. In this 

 process, the mercury is displaced from solution by the copper and 



Fig. 4 — With this electrolytic cell as little as a milligram of various heavy metals 

 may be precisely determined. 



