A STUDY IN MORBID AND NORMAL niYSlOLOGY. 163 



Case Y. — Pneumonia. 



Incremknt of 

 No. Datb. Temp, of Temp, ob Pulse. Temp.';kature KEM.\RKS. 



Ward. Patiknt. in Ualoiu.veteu. 



(Cent.) ICeiit.) (Cent.) 



190.5390.7-400.5 100 C0.14 Male, set. 30, weight 130 pounds. 



19.9 40.3 100 0.175 



19.5 39.3-38.4 100 0.225 



19.5 40.2 lOS 0.23 



17 normal normal 0.11 ' 



Thf- conclusions drawn by Leydcn from his experiments are: Tlie dissipation of 

 heat is increased in fever, both when tlie bodily temperature is constant, wlicn it is 

 increasing, and when it is diminishing; consequently there is without doubt in- 

 creased heat production in fever. In the highest fever the rate of eiviu" off of 

 heat is almost double the normal standard. Heat dissipation reaches its maximum 

 in critical periods when the temperature is rapidly falling; under these circumstances 

 it may be three times as rapid as normal. This rapid critical dissipation occurs with 

 profuse sweating, whilst in fever with rising temperature there is no perceptible 

 production of water even under an impermeable clotli. (^^'ahrend bei ansteigendem 

 Fieber iiberliaupt kcine Wasser Production selbst unter einer imperspirabeln Decke 

 nachweisbar ist.) In epicritical states the heat dissipation sinks below normal. 



Prof Sanderson objects to these conclusions of Leyden. I quote from him in 

 exleaso (p. 56). 



"The careful study of Profes.snr Lej'den's results has led me to an interpretntion which differs 

 materially from that which he lias enibodied in his main conclusion. Ho admits, tlu-oughout, the 

 great importance of visible perspiration, ?'. e., of the secretion of watery fluid by the sweat glands as 

 a condition favoring the discharge of heat from the skin. He points out that in all those of his 

 experiments in which the heating of the calorimetrical water was most rapid, the result could be 

 connected with rapid cooling of the accessible parts of the body, and witli profuse sweating. But 

 he finds there were cases in which, notwilhstanding the dryness of the skin, the fevered body parted 

 with its heat to the calorimeter with a rapidity which could not possibly be accounted for as the 

 mere result of the greater heat of the surface. In looking through the cases I am unable to find a 

 single instance in which, the state of the skin being noted, it was found that, in the absence of per- 

 spiration, the loss from the surface was considerably in excess. This being so I am compelled to 

 associate increased dischai-gc from the surface not with pyrexia, but with sweating, for while on the 

 one iiand I find instances in which the patient was in high fever, with only an average of heat loss, 

 I find in the same patient on another day a very active discliarge of heat from the surface, but no 

 fever. 



"In so tar as can be shown that the increased rate at whicli the fever patient's heat was coramu- 

 nicaled from the limb to the calorimeter in which it was inclosed is dependent on sweating, the re- 

 sult is of little value or significance as an index of increased production of heat in the living tissues. 

 Under the condition of the experiment, *. e., when a limb is inclosed in an air-tight chamber, the air 

 which occupies the space between the cutaneous surface and that of the chamber soon becomes 

 sat.ura,ted with moisture. As soon as this state of things is established there is no further loss of 

 heat by the conversion of sweat into vapor; the effect of sweating therefore resolves itself into the 

 more abstraction of the limb to a certain quantity of watery liquid of which the whole of the heat 

 goes into the calorimeter. So far as the body of the patient is concerned, the process is attended 

 with the loss of a certain quantity of water, "and manifests itself in a corresponding loss of weight, 

 but so far as relates to the chemical processes by which heat is ])rodueed, it fails to afford any in- 

 formation. If for every gramme of water sweated out at the surface, it were the law of the animal 

 economy that an equal quantity of cold water should be ingested, then it might be said with truth 



