370 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



The tubes are made in the form shown in Figure 5, the lower end 

 being as in Figure 8. 



The part a is about 6 cm. long, e is left open for the insertion of the 

 capillary. This capillary is held in place by a platinum clip shown de- 

 veloped in Figure 7. The end b is left open for the attachment of the 

 distilling apparatus ; c is drawn out, being left large enough for safe 

 handling. After the insertion of the capillary, care being taken to 

 centre it accurately in the tube g, the part d is drawn down as shown in 



^J 



f 

 Figure 6. 



<•> 



Figure 7. 



Figure 6. The heavy liquid is now placed in the tube g and the end e 

 bent over for attachment to the pump. The lower end of the tube 

 as well as the method of holding it in the steel chamber is shown in 

 Figure 8. 



L is a large steel chamber (capacity 20 cm.) containing pure mercury ; 

 K\s a stuffing-box screwed down on the rubber packing g. The glass 

 tube / is inserted in the heater down through the hole in the bottom. 

 The piece /is slipped on, then the steel washer e, and finally a rubber 

 stopper c. By slightly moistening the tube with glycerine, the stopper 

 may be worked over the enlargement M. Then J is screwed down and 



