APPENDIX A. 229 



Experiments on the tension of steam with a 

 boiler, and a thermometric tube full of air. A 

 thermometer will be placed in a tube immersed in 

 the boiler, open outwards and filled with oil or 

 mercury. 



Experiments by means of a simple capillary 

 tube filled with three successive parts first of air, 

 second of mercury, third of water or other liquid 

 of which the tension can be measured (of alcohol, 

 of ether, of essence of turpentine, of lavender, of 

 sulphide of carbon, of muriatic ether, etc.). 

 One end of the tube may be immersed in a bath 

 of mercury or oil, the temperature of which is to 

 be measured. The column of mercury can be made 

 long enough to allow of the air being previously 

 compressed or rarefied. 



FIG. 6. 



The tube will be bent into a spiral at one end, 

 the straight part being graduated (thus permitting 

 the tension of mercurial vapor to be measured). 



Experiments on the tension of vapors at low 



