364 Dr Davy on Animal Heat. 



monly is so very different, it may be answered, that in all these 

 classes such a constitution of blood-corpuscle may be designed 

 for the same end ; and that birds partly owe their high tempe- 

 rature to it ; and that in reptiles and fishes, in most of which 

 the proportion of red particles is small, were the constitution 

 of blood-corpuscle different, it would be inadequate to perform 

 the part required of it. 



2. On the Temperattere of Man in advanced age* 



Not aware of any observations having been published on 

 the temperature of man in advanced old age, I have been in- ■ 

 duced to institute some trials, the results of which I shall 

 now briefly describe. 



1. 91 years of age ; feeble on his legs, but in pretty good 

 health; a native of Grasraere, in Westmorland, where he 

 has always resided, in easy circumstances, cultivating his own 

 land. In June, when the temperature of the air was 60°, a 

 thermometer placed under the tongue rose to 99°-5; his hands 

 were warm ; his pulse at the wrist 48, strong, intermitting. 

 The observation was made at 2 p.m. ; he had dined at noon. 

 On the 28th of the October following, his temperature was 

 again tried, about the same time of day, when the open air 

 was 42°, the air of his room 52° ; now, under the tongue, the 

 thermometer was 98°.5 ; the pulse 56° ; his state of health 

 much the same as before. 



2. 88 years of age, also a native of Grasmere, where he 

 has mostly resided, as a day labourer ; is pretty firm on his 

 feet,, but troubled with chronic cough and difficulty of breath- 

 ing. In June, when the temperature of the air was 60°, a 

 thermometer placed under the tongue rose to 99°. 5 ; his pulse 

 was 56, and rather feeble ; he had dined three hours pre- 

 viously. On the 28th of October, an hour after dinner, when 

 his pulse was 70, the thermometer under the tongue was 98° ; 

 the air of the room 55°. In February, about three hours after 

 dinner, when his pulse was 44 and feeble, the temperature 

 under the tongue was 96°. This was on the 27th ; the air 

 then of his room was 44° ; the open air about 32°, after a 

 heavy fall of snow, and a sharp frost of several days' dura- 

 tion. The old man was feebler than in the summer and 



