628 



SEC. 13. CHEMISTRY. 



cock o is opened, but n and m are shut, and the floating piece is, by the help 

 of the millimeter-scale t, placed so as to give the desired rarefaction. 



The regulator may also be employed -with a distilling apparatus in connec- 

 tion with the rarefied air. In this case, one india-rubber tube is put in 

 connection with one end of the air-tight apparatus of distillation, and the 

 other india-rubber tube is put in connection with its other end. 



2578. Collection of Burettes and Burette Stands. 



Dr. H. Geissler, Bonn. 



2579. Collection of Pipettes, with stand. 



Dr. H. Geissler, Bonn. 



