$jj On the "Freezing of Mercury, &c. 



alarmed at the dead appearance of the parts that had been fo 



fuddeftly robbed of heat by the frozen metal *. 



The larger pieces were kept for fome minutes before fufion 

 took place, while others were twifted and bent into various 

 forms, to the no fmall gratification and furprife of thofe who 

 had never witneffed or expected to fee fuch an effect pro- 

 duced on fo fufible a metal. 



Though mercury in the ftate in which we had it, exhi- 

 bited a considerable degree of ductility and malleability, we 

 cannot thence infer the degree in which they would be 

 found to belong to it, could it be reduced to a temperature 

 much more considerably under its freezing point, which 

 feems to he at about — 39° or — 40°. At the time that we. 

 bent and twifted it, it may be confulered as having been in a 

 proportionate temperature to iron near its point of fufion, 

 when, as is well known, it will hardly bear the fmallelu 

 blow of a hammer. 



As the apparatus employed in thefe experiments was ex- 

 tremelv fimple, a fliort defcription of them may not be un^ 

 acceptable. Fig. 1 [Plate II.) reprefents that employed in 

 the firft experiments) and only viewing the figure will con- 



' * It was a ccnfiderable time before fenfatien and the natural colour was 



rcftored to the parts, which however returned without any other means 



:.*[>; .y:.l than fuch as have been mentioned. It is eafy to conceive 



that the injury was little more than Ikta deep, like what takes place from 



rouehin - a hot metal, without allowing it to remain long enough in contact 



with the fk'm to produce a wound ; but what is very fingular, aimed every 



individual compared the fudden pain he experienced to that produced by a 



turn or feedd! One gentleman, who called accidentally while we were 



preparing for our experiment, but who had no acquaintance with the fub- 



ieft not being able 10 conceive how the erl'eit propofed could be produced 



fcy the mixture, was dcfired to take a little (now in one hand and muriat 



of lime in the other: " they were neither of them colder than he expected 



to find them :" then to put the mow into the hand that held the muriat. 



The ingredients had hardly come in contact when he threw them from 



•trim, exclaiming, « Cold !— Th a red-hot cob! I" 



vey 



