7 S 6 ANIMAL HE A T. 
nionieter was due to Celsius in 1742. 1 Throughout this article the centigrade 
scale is employed. 
The Determination of Temperature in Different Parts 
of the Body. 
Varying quantities of heat are produced and lost in different parts 
of the body, and although the circulation of the blood tends to bring 
about a mean temperature of the internal parts, local differences are 
present. It is important, therefore, that the determinations should be 
made in those parts which have a temperature representing the internal 
temperature ; and in order that the results may be comparable, the 
observations should as far as possible be made in similar anatomical 
positions. 
The most suitable place for the application of the thermometer 
varies under different conditions, and methods have to be considered, 
not only in as far as they are scientifically sound, but also in respect to 
their ease in practice. 
The rectum naturally otters the readiest access to the internal parts, and 
thermometers with or without a metal guard may be safely introduced 5 or 
6 cms. This method is the most suitable in the case of animals, and may be 
advantageously employed in infants. The vagina, uterus, and bladder of 
women and female animals of suitable size have a similar value to that of the 
rectum. 
In order to obtain the internal temperature of the body, the bulb of the 
thermometer, previously warmed in the mouth, may be inserted in the stream 
of urine as it leaves the urethra. 2 Apart, however, from the limited applica- 
bility of this method, there is a danger of a loss of heat by evaporation and 
radiation, but with care excellent results may be obtained. 
The axilla is a convenient place for thermometric determinations in man, 
for it is not liable to great variations in temperature. It is necessary, how- 
ever, that the axilla be closed well and long enough for it to attain the 
temperature of a closed cavity : in very thin or wasted subjects it is difficult 
to effect this, and the temperature should therefore be taken elsewhere in such 
cases. 
The groin has also been selected by some physicians for the observation of 
temperature, but in man it is not so easy to retain the thermometer in the 
fold of the groin as in the closed axilla. The method is useful in the case of 
infants. 
The mouth, on account of convenience, has heen widely selected for the 
clinical observation of temperature, but the readings of a thermometer, even 
when the bulb is placed under the tongue and the mouth is firmly closed, are 
liable to be low, owing to the danger of cooling of the tissues of the mouth, 
externally by cold air, internally by the inspired air. The mouth is also liable 
to considerable local variation of temperature. 
In order to obtain accurate results, the thermometer should be retained for 
eight minutes in the mouth, ten minutes in the well-closed and dry axilla, and 
1 For an account of the introduction of the thermometer into clinical use, see Wunder- 
licli, "Medical Thermometry," New Sycl. Soc. Translation, 1871, p. 19; Lorain, "De la 
temperature du corps humain," Paris, 1877, tome i. p. 39 et seq. 
- Stephen Hales, "Statical Essays," London, 1731, 2nd edition, vol. i. p. 59 ; Martine, 
"Essays, Medical and Philosophical," 1740, p. 335 ; Blagden, Phil, Trans., London, 1775, 
vol. lxv. pt. 1, p. 114 ; Davy, ibid., 1844, pt. 1, p. 63: Mautegazza, Prcssc mid. beige, 
Bruxelles, 1863, tome xv. p. Ill ; Oertmann, Arch. /. d. qcs. Physiol., Bonn, 1878, Bd. 
xvi. S. 101. 
