118 



T. G. KINGSFORD, NOTE ON A NEW METHOD OF 



strips of rubber (d) are !solutioned on to the rubber lining of the- 

 above band to form distance pieces, keeping the glass sides the 

 desired distance apart. Fig. 1 will, I think, make this quite clear. 

 It shows a tank ready for use, and intended to be attached to an 

 ordinary bull's-eye condenser stand. 



In the construction of these tanks it will be seen at once that 



Fig. 1. 



the most important thing is to be able to obtain glass discs with 

 fairly true edges, as the water-tightness depends entirely on the 

 glass sides making a good joint with the rubber-lined metal band. 

 This apparent difficulty is easily overcome, as there are already on 

 the market the very articles that we require in the form of bevel- 

 edged clock-glasses. These can be obtained in sizes from about 

 |-in. diameter to about 8-in. diameter through any clockmaker,. 

 and if the best quality is specified they will be found to have 

 perfectly true edges, nearly as sharp as a knife, and therefore 



