52 



L. CASELLA'S CATALOGUE 



FIG. 242. 



FIG. 252. 



FIG. 264. 



The thermometers Nos. 236* to 239 are all contained in tubes of % or ^j-inch. diameter ; and 

 the bulbs are narrow and cylindrical, to permit the passage of the thermometer through corks 

 for insertion into retorts, etc. 



240. Thermometers as above, with two scales, Fahrenheit and Centigrade, Is. 6d. each 

 more than if one scale only. -y ( 



242. Chemical Thermometers of greater precision, all glass (fig. 242), etched on the 



stem for more delicate experiments scales Fahrenheit or Centigrade 8 inch, in 

 paper case to 212 Fahrenheit, 100 Centigrade . . .076 



243. CHEMICAL THEEMOMETEB, 9-inch, to 320 cent. . . .090 



244. CHEMICAL THEEMOMETEE, 12 to 15-inch, to 650 Fahrenheit=320 cent. 11 6 



245. CHEMICAL THEEMOMETEE, 25 inches long, filled with pure alcohol, tube very 



carefully calibrated, divided and figured on stem from 100 below zero to 90 

 above (or as required) in brass case . . , . 1 10 



246. Chemical Registering Thermometer, improved on Professor Phillip's principle 



for registering high temperatures in any position 15 6 to 1 10 



