Heat. 459 



rit of wine, in the violet near the blue ; with the water 

 in the middle of the violet ; with the oil of cassia 23 lines 

 bevond the violet border. — {Baumgartner s Zeitschrift. iii. 

 336. 



Dilatation of absolute alcohol and sulphuret of carbon, by 

 heat. Professor Muncke, of Heidelberg, has made expe- 

 riments, during several winters, to determine this point 

 accurately. He also studied the dilatations of pure water, 

 artificial sea water, sulphuric ether, petroleum, ammo- 

 nia, muriatic acid, nitric acid, sulphuric acid, and almond 

 oil ; he found their maximum density to exist at the follow- 

 ing temperatures : 



Pure water 38-80 F. 



Artificial sea water 22*55 



Alcohol not pure (sp. g. 808 at 54|°)— 69-8, or— 56-6 C. 

 Sulphuric ether (sp. g. 733 at 54i°)— 32-8 

 Petroleum (sp. g. 78-125 at 541°)" —96-7 

 Absolute alcohol (sp. g. 791 at 32°)— 129-1 

 Muncke found that he could heat sulphuric ether in a 

 straight thermometer tube up to 107-6°, without boiling, and 

 once as high as 122° ; rectified petroleum he raised to 212°, 

 without boiling it ; and sulphuret of carbon to 149°; al- 

 though the common boiling temperature of these liquids 

 are 95°, 185°, and 116°. He attributes this phenomenon, 

 which has been previously observed, to the adhesion of the 

 liquid to the sides of the tubes, and to the difficulty of eva- 

 poration. Muncke concludes, from his experiments, that 

 petroleum is much better adapted for thermometers than 

 alcohol ; but that sulphuret of carbon is still better. Pe- 

 troleum must congeal below — 95°, and sulphuret of carbon 

 still lower; neither of them has been solidified. The sul- 

 phuret, when well made, is always of the same quality. 

 The order of their dilatations at 122° is, sulphuret, 60723, 

 Petroleum, 56071, Alcohol, 52632* 



Temperature of carbonic acid disengaged from different 

 sources. — Bischof disengaged carbonic acid from carbonate 

 of lime, by exposing it to a strong heat in a cannon. A 

 thermometer placed in the current of gas, at the muzzle, 

 rose up to 88^°, and remained there, whatever intensity 

 was given to the heat. In another experiment, he disen- 



* Memoires de St. Petersbourg, ii. 1335 — 36. 



