116 ON THE FLEXURE OF WAX, &C. 



fo as (o remain in the pofition reprefented in Fig. 1. in which 

 ilate it is ready for being pafled down the oefophagus ; and ifc 

 feems fcarcely neceflary to remark, that previous to the inftru- 

 ment being withdrawn, the cap C muft be pulled off, by mean* 

 of the thread at A ; when the wires will expand the net, and 

 prefs its edge clofe to the gullet on every fide, and in return- 

 ing to the mouth, will probably bring up any fubftance that 

 was lodged there, within it. 



G. C. 

 Brompton, Jan. 23, 1803. 



VIII. 



On the Flexure of Wax and other Bodies by irregular cooling, 

 with Confiderations on the Probability that it may be caufed by 

 the Law of Cryjlallization. In a Letter from R. B. 



To Mr. NICHOLSON. 



London, Feb. 16, 1809. 

 SIR, 



Thread of wax "- STREAM of wax has juft overflowed the cup of the 

 flowing down a wax candle by which I have been reading, and has prefented 

 me with a facl or two which I think worthy the meditation of 

 philofopheis. If you think fo, pleafe to give them a place in 

 your repofitory. 

 becomes fepa- The fluid wax has formed a line or protuberance on the out- 

 "ejus flexure. "^ e °^ tne canc Me, four inches in length, a little more than 

 one fifteenth of an inch in width, or furface applied to the 

 candle, and one tenth of an inch in elevation or thicknefs. 

 As it grew cold it has feparated from the candle, fo that its 

 lower extremity ftands a little more than half an inch diitant, 

 and it does not touch for the length of two inches and a half 

 irom the bottom ; all the upper part full continuing adherent. 

 And laftly, the feparated portion exhibits a regular curve, 

 convex towards the candle, and more convex the nearer the 

 lower extremity j fo that, when carefully taken off, and ap- 

 plied to feveral circular arcs defer ibed upon paper, the diffe* 

 rence was very obvioufly perceived. 

 The wax was Upon thefe facts I obferve from obvious reafons that the 

 xenVparts in ** w » x which flowed in contacl with the folid candle, was more 

 fucccflion. fpeedily 



