igS PHILOSOPHICAL TRANSACTIONS. [aNNO 1792. 



into the bath; but this was running too great a risk, unless some more sudden 

 and certain method could be found of restoring the heat that might be lost. It 

 was prudent therefore to proceed more cautiously. In the next experiment I re- 

 solved to try the methods of heating as well as cooling the body. 



Exfer. 3. The following day, at the same hour, the same person was again 

 immersed in the salt-water bath. His heat previously was 98°, his pulse 100. 

 The temperature of the air and the atmosphere, as before, 44°. The mercury 

 sunk rapidly to 90°. 



2 mill, after immersion 88° 7 min. after immersion 92° 12 min. after immersion 95° 



3 88 8 94 13 96 



4 88 i 9 94. 14. 96 



5 90 i 10 94 ^ 15 96 



6 92 ' 11 94 I i6 96 



He was now taken out, and stood in the wind 3"*, shivering violently. This 

 circumstance rendered it difficult to ascertain exactly the fall of the mercury, 

 which was however considerable. When examined in the room in which he un- 

 dressed, it stood at go°. He was now plunged into a fresh-water, warm bath, 

 heated to 97°^. What is very surprising, the mercury fell 2°. The following 

 table will show the progress of the return of his heat. 



1 min. after immersion in the 4 min. after immersion 9*° 1 min. after immersion ^&^ 

 warm bath, mercury .... 88° 5 94 8 Cfi 



2 mmutes 92 6 <j% 9, 10, 1 1, 12, to 16 ... 96 



3 92 



If the rise of heat in the cold bath at 44°, and the warm bath at 97°4, be 

 compared, the first will be found more slow; but that after being l6"^ in the one 

 and in the other, the heat was the same in both cases, when taken at the 

 mouth. It must however be acknowledged, that in the cold bath, the extremi- 

 ties were chilled and cold, while in the hot bath, the heat was equally diffused. 

 When Edwards got out of the hot bath, he put on his clothes, and was re- 

 markably alert and cheerful the whole evening. Encouraged by the safety of 

 these experiments, I resolved to increase the time of immersion in the cold bath, 

 and to inquire more generally into its effects on the sensations, as well as heat. 



Exper. 4. At the same hour of another day, the same person was again im- 

 mersed as before, his heat previously being 97°-^-, and that of the water 42°, 

 Wind north-east, and brisk. 



1 minute after, . . heat 90° 6 minutes 92°^ 15 to 24 9i°^ 



2 minutes 92 7, 8, 9, 10, 1 1 94 25 94 



3 92 12 00 26, 27 00 



4 92 i 13 00 28 94 J 



5 92 14 94 J 29, 30 94 



It will be observed, that in the above table there are blanks left in the report. 



