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SUMMARY OF CURRENT RESEARCHES RELATING TO 



seen in tlie drawing), and fits into a groove in the glass slide a. A pin d 

 also fits into a hole at the end of the groove. The rod is heated by a 

 spirit-lamp.* 



Fig. 62. 



Fig. 63. 



Prof. Strieker's more complete form f is shown in fig. 64. It consists 

 of a block of black vulcanite 3 X 1^ X 1/4 in. The central cylindrical 

 chamber h is closed below by a glass plate and surrounded at the top by 

 a copper disc a. The bulb of the thermometer passes round the chamber, 

 as shown by the dotted line d. Its capillary tube lies in a trough, one 

 side of which is formed by the back of the block and the other by a 

 metal plate screwed to it, the form of which is shown in the fig. The 

 tube c (for gases) leads into the chamber, and a second tube leads from it 

 through the projecting metallic arm shown at the top. This arm, which is 



* Burdon-Sanderson, op. cit., fig. 12. 



t Strieker, op. cit., pp. xvii.-xviii. (1 fig.). Burdon-Sauderson, op. cIt., p. 7 (fig. 2). 



