CONTRACTION OF WATER BY HEAT. 



This very tall jar was placed on a table, with the Interpol!- 

 tidn of Tome folds of thick paper, in a *oom without a iire, of 

 (he temperature 42°. 



I filled it with water of 50°, and- poured into the bafon, 

 which embraced the lop, a mixture of powdered ice and fajt. 



From time to time I explored the temperature near the fur- 

 face, by infertmg the/huib of a thermometer, to the depth of 

 half an inch nearly in the axis. - . '■ .. 



fiottbrai Trtp. 

 '50°^ 50° 



3» 



One o'clock, 

 In 11 'minutes', 

 ___ 15 • 



: „2i — i — - 



— 31 -— 



— 41 ! — , 



— 1 hour 6 min. 

 - _ 1 — 2 o _^- 



Au i . 44- — 



— 4^§ hours, 



• Air. 



The experiment 

 tafted 50hotift* 



— 5| hours, 



— 1 1 hours 



at mid 



jrs, j. e.~\ 

 idnight, J 



i) |. e. "1 



>rning, J 



19 noun 



next morning, 



4'5 ■ 

 ***** 

 4-2 • 

 41 



40- 



39.5 



49.5 



39.5 



39 

 39 



39 



•* .AS- 



44 

 '42 



' pUihistimeatlrinfilmof 

 34- \ ice "bega.n to form in €0n- 



. |_tacl with .the gfafs. 

 34 



f A cruft of ice of fome thick- 

 < nefs now lined the glafs, 

 l^and air had fallen to 40°, 



Cruft of ice complete. 

 Air 40°. 



— 26 hours, 



— 32 



40 

 40 



40 

 41 



!Air 40°. So much ice had 

 melted that the cake was de- 

 tached from the (ide of the 

 veffel, and floated. 

 Air 4l c \ Ice not all melted. 

 Air 42°. Ice not entirely gone. 



This long protracted experiment prefents fome ftriking facts, Review of trie 

 and its general import, with regard to the fubject: of inveftiga- fa ^ nd r *" 

 tion, agrees with the preceding. In it we fee, that when the 

 frigortfic mixture abftraded caloric from the upper extremity of 

 a cylinder of water, nearly 18 inches long, and at-50 p >'lhe re- 

 duction of temperature appeared fooner, and advanced quicker, 

 at its lower extremity than in the axis at the top, not two and a 

 5 half 



