1894.] ic ith a Fused Electrolyte and a Gaseous Depolarizer. 50 



FIG. 3. 



was an open tube. The electrolyte was a fused mixture of equivalent 

 proportions of NaCl,KCl. A porous pot was introduced in order to 

 separate the products of electrolysis set free at the electrodes. The 

 chlorine gas was supplied through a clay tube, which passed down 

 the centre of the carbon tube. As before, an iron crucible was used 

 as the containing vessel for the fused lead and the electrolyte, it also 

 served as a means of electrical connection with the lead. In relation 

 to the depolarisation effect of the chlorine, which it was the principal 

 object of the experiment to observe, the interfering action of the iron 

 was found by comparison with porcelain to be practically nil ; this no 

 doubt is a consequence of its becoming coated by local action with a 

 film of lead. The whole arrangement was heated in a reverberatory 

 furnace. "When the electrolyte was perfectly fused, the element was 

 short circuited through a volt-meter of 1000 ohms resistance. An 

 E.M.F. of 0'3 volt was observed, the outside current being from the 

 carbon to the lead. This was the E.M.F. after polarisation. A 

 current of chlorine was then passed through the earthenware tube ; 

 rhile the current of gas was slow there was no effect, but when the 

 speed of the issuing gas was increased until the gas passed in bubbles 

 ilong the side of the carbon, alternately surrounding it with chlorine 

 and electrolyte, the E.M.F. rose to 1'25 volt. The action of the cell 

 then similar to a completely depolarised cell. When short 

 circuited through a low resistance ammeter, it produced a steady 

 current of 1*0 ampere for three-quarters of an hour. The potential 

 lifference between the poles was of course very small, while this 

 current was passing, the exterior resistance being very small com- 



