TOL. LXXXII.] PHILOSOPHICAL TRANSACTIONS. 205 



bath was then heated to 95 and 96°, but still he felt cold. It was heated to 99°: 

 he continued in it 5*", and his heat was 91°. The heat was gradually raised to 

 106°, when the sense of coldness, of which he had complained at the pit of the 

 stomach, gradually went off. Before this I had usually kept him in the warm 

 bath till his natural heat was nearly recovered, but after being half an hour in the 

 heat of 106°, his own heat was still 93°. He now became sick and very languid, 

 a cold sweat covering his face, his pulse very quick and feeble. He was removed 

 into bed, but passed a feverish night, and next day had wandering pains over his 

 body, with great debility, resembling the beginning stage of a fever. By cordials 

 and rest this went off. This expt. clearly enough confirms the greater danger of 

 being wet with fresh than salt water ; but in itself points out nothing certain be- 

 sides, except that it is not to be rashly repeated. The thermometers I employed 

 had not a sufficient mobility for very nice experiments, and I am well aware that 

 in particular instances this may have misled me, though the general results, which 

 is all that is of importance in such expts. as these, will, I hope, be found just 

 and true. 



Before concluding, I must offer a few observations on the subject that led to 

 these expts. 1. It is, I think, already well known among seamen, that where 

 there is only the choice of being wet with salt or fresh water, it is always safest 

 to prefer the first. In the heavy showers of rain, hail, or snow, by which gales 

 of wind are generally accompanied, the men that must be exposed to them, ought, 

 like Lieutenant Bligh and his crew, to wring their clothes out of salt-water. 



2. In all cases where men are reduced to such distress by shipwreck or other- 

 wise, that they can only choose between the alternative of keeping the limbs con- 

 stantly immerged in the sea, or of exposing them to the air while it rains or 

 snows, or the sea is at times washing over them, it is safest to prefer a constant 

 immersion ; because in the northern regions, where the cold becomes dangerous 

 to life, the sea is almost always warmer than the air, as the expts. of Sir Charles 

 Douglas show ; and because there is not only a danger from the increased cold 

 produced by evaporation, but also from the loss of heat by the rapid changes of 

 the surrounding medium, as the foregoing expts. point out. 



3. Whether, in high and cold winds without rain or snow, and where a situa- 

 tion may be chosen beyond the reach of the waves, it is safer to continue in the 

 air, or to seek refuge in the sea, must depend on several circumstances, and can- 

 not perhaps be certainly determined. The motives for choosing the sea will be 

 stronger in proportion as the wind is high and cold, and in proportion as the 

 shore is bold. 



The foregoing narrative shows that men may survive 23 hours immersion in 

 the sea, of the temperature of 38° or 40° (as great a cold as it almost ever possesses) 

 without food or water, and almost without hope of relief; but that any man ever 



