Body temperature and comfort
J. Argyll Campbell published “Body Temperature and Comfort” in 1919 in the Journal of the Straits Branch of the Royal Asiatic Society, presenting a six-year personal physiological study tracking his own axillary and mouth temperatures across six climates—Scotland, Singapore, Java, Perak, and Australia—to demonstrate that a rise in body temperature to 97.6°F, even in the absence of fever, produces significant discomfort and that architectural siting and ventilation are the decisive factors in tropical comfort.
Summary
Campbell’s study is a self-experimentation exercise in which a single healthy male subject (aged 34, 5 ft. 9 in., 10 stone 4 lbs.) had his axillary and mouth temperatures recorded daily under controlled conditions across six residences over a six-year period. The methodological framework is straightforward: the same clinical thermometers were used throughout, readings were taken in the same room each time, and the subject maintained a consistent daily routine of meals and exercise. The central question is not whether tropical heat causes fever, but whether sub-febrile elevations in body temperature—below the clinical threshold of 98.45°F—produce measurable discomfort and, by extension, long-term health damage.
The most instructive comparison in the paper is between two Singapore bungalows with nearly identical atmospheric conditions (wet bulb 76.3° vs. 76.7°; dry bulb 81.4° vs. 81.5°). Bungalow No. I, situated on a hill about 150 feet above sea level with a constant cool breeze, yielded an average axillary temperature of 97.1° and the subject “very rarely felt uncomfortably hot.” Bungalow No. II, at near sea level and enclosed by hills and dwellings on three sides, produced an average of 97.6° and consistent discomfort. Campbell attributes the difference entirely to the absence of breeze, which impairs convective and conductive heat loss from the skin. He extends this argument to a public-health claim: in the thickly populated, still-air areas of Singapore, the combination of heat and moisture exerts its “greatest ill,” and the city’s high death rate is a consequence.
The paper draws on O’Connell’s 1913 work on malaria etiology and on the H.M. Chief Inspector of Factories’ observation that a rise in mouth temperature becomes perceptible when the wet-bulb temperature exceeds 75°F. Campbell’s own data confirm this threshold: both Singapore bungalows exceeded 75° on the wet bulb, but only the still-air bungalow produced sustained discomfort.
Key Findings
- The subject’s axillary temperature averaged 97.0° in Edinburgh (mean annual atmospheric temperature 47.7°) and 97.1° in breezy Bungalow No. I, Singapore (wet bulb 76.3°, dry bulb 81.4°)—demonstrating that a well-sited tropical residence can match temperate-climate body temperatures (p. 64, Chart VII).
- An axillary temperature of 97.6° was the consistent threshold for “uncomfortably hot” sensation across all climates; this occurred in Bungalow No. II, Singapore, and intermittently at Lembang, Java, and Taiping Hill (pp. 64–65).
- Bungalow No. II, Singapore, recorded an average mouth temperature of 98.3°—above the standard mean of 98.45°—despite atmospheric readings nearly identical to Bungalow No. I, confirming that still air, not ambient temperature per se, drives the elevation (p. 64, Chart VII).
- At Lembang, Java (4,000 ft. elevation), the average axillary temperature was 96.7° with wet-bulb readings of 64.7°; at Taiping Hill, Perak (3,400 ft.), it was 96.9° with wet-bulb 68.7°—both comfortably below the discomfort threshold (pp. 64–65).
- The H.M. Chief Inspector of Factories’ threshold of 75° wet bulb for perceptible rise in mouth temperature was exceeded in both Singapore bungalows, but only the still-air bungalow produced sustained discomfort (p. 65).
Conclusion
Campbell’s definitive takeaway is that in a warm, moist climate, the single most important variable for bodily comfort is not the ambient temperature but the availability of air movement. A properly sited, breezy residence in Singapore can maintain body temperatures indistinguishable from those in Edinburgh, while a poorly ventilated, still-air dwelling at the same latitude and with the same atmospheric readings will push body temperature into a range that produces chronic discomfort and, over time, “considerable damage to health.” He recommends hill sites, maximum use of available breeze, and the installation of electric fans in all buildings.
Context
- Campbell writes from the position of a resident medical practitioner in Singapore, referring to “our town” and “our high death rate” as matters of local administrative concern (p. 65).
- The study draws on standard British physiological references (Pembrey/Schafer’s Text Book of Physiology) and O’Connell’s 1913 paper in the Journal of Tropical Medicine and Hygiene, situating it within the colonial public-health discourse on tropical disease etiology and factory hygiene.