34<5 



CONTRACTION OP WATER BY HEAT, 



change of tern 

 perature would 



the fame conclufiou would follow ; while a different inference, 

 and the exiftence of the fuppofed anomaly, would be deducible 

 the bottom, if fhould the event prove different. The only circumftance, I can 

 denfeft,through. fig are i myfelf as tending in any meafure to render this mode 

 •ut filch change. ? - • , , , r, . , 



ot examining the point doubtful, is, that water near its congeal- 

 ing point may have fo little change of denfity occasioned by a 

 fmali variation of temperature, that its particles may be prevent- 

 ed by their inertia, or by the tenacity of the circumfluent mafs, 

 from afiuming that fituation which their fpecific gravity would 

 allot to them. 



It will appear, however, very clear, from the circumftances 

 of the experiments which I fliall immediately detail, that no 

 obflacle to the fuccefs and precifion of the experiments pro* 

 ceeded from this fource. 



It is not neceflary for me to relate all the experiments I have 

 made. I fliall reftricl myfelf to the detail of fix, which prefent 

 varieties in the modes of procedure, and which afford the mod 

 ftriking refults. 



Exp. 1. 1 filled a cylindrical jar of glafs 8f inches deep, and \\ 



in diameter, with water of temperature 32°, and placed it on 



Exp. ¥. Ice- 

 cold water ex- 



Itmofphere, was a table, interpofing a confiderable thicknefs of matter poffeffed 

 warmer |i£) G f little power of conducting heat. 1 fufpended two thermo* 

 meters in the fluid, nearly in the axis of the jar, one with its 

 ball about half an inch from the bottom, the other at the fame 

 diftance below the furface. The jar was freely expofed to 

 the air of the room, the temperature of which was from 60"* 

 to 62°. 



The experiment commenced at noon : 



Top Thermom 



below till 38' 

 after which it 

 was warmer at 

 top. 



In. 10 minutes, 



__30 



_50— 



— an hour, 



i and 10 minutes, 



— -. 30 



50 



— 2 hours and 10 minutes, 



, _ 30 * 



i .50 , 



— 4 hours, 



32* 



33+ 



35.5 



37 



38 



42 



44 



46 -f 



43 



50 • 



30.5 



54 



Bottom do, 

 32° 

 34-f- 

 37 



38-f 

 38-f 

 38.25 

 40 

 4T-f 

 42.5 

 44 

 45 

 49 

 Confiding 



