45, CORNHILL, E.G., AND 122, REGENT STREET, W., LONDON. 



483 



FIG. 2918. 



Each. 

 s. d. 



2949 Glass Flask, mounted with brass stop-cock, for experi- 



ments with heat under diminished pressure (fig. 2446, page 470) 



2950 Cubical Tin Vessel, (Leslie's Cube), with stop-cock, to 



illustrate the expansion of water into steam by heat 

 and contraction (or condensing) by cooling 



2951 Air Thermometer, for ascertaining very small differ- 



ences of temperature by the expansion of air. 

 Invented by an Italian Physician, Santorio, in the 

 Seventeenth Century (fig. 2251) 15 



2952 Leslie's Differential Thermometer (fig. 2952) . . 1 10 



2953 Wollaston's Boiling Point Thermometers (see pages 92 to 94.) 



2954 Tyndall's Apparatus, to demonstrate the production of 



Heat by friction. See also No. 2144, page 492 



2955 Thermometers (fig. 2955), various, and for High 



Temperatures, Iron, Brass, or Copper mountings. 



Each. 

 s. d. 



10 6 



10 6 



110 



220 



660 



(See page 1G7.) 



