2 The Philippine Journal of Science wit 



Experiments have been made almost daily for more than six 

 months, including the hottest month known in Manila in six 

 years (April, 1912). Twenty-three monkeys have been em- 

 ployed thus far. 



The method of study was as follows: After a preliminary 

 study of the variation of the monkey's body temperature in the 

 shade, the monkey was placed in the sun rather early in the 

 morning, and during the exposure, frequent observations were 

 made of the pulse, respiration, and body temperature. Other 

 symptoms were also looked for, such as position assumed, mois- 

 ture of the skin, and signs of discomfort. Observations were 

 also made upon the temperature of the atmosphere surrounding 

 the monkey and the temperature of the surface upon which or 

 near which it rested. The humidity of the atmosphere, reading 

 of the black-bulb thermometer, and the amount of sunshine, as 

 well as the velocity of the wind, were also noted. Monkeys were 

 placed on the ground, on the asphalt roof of the laboratory, or 

 upon slender poles raised above these surfaces. During the 

 experiments the monkeys were kept upon a constant diet that 

 seemed to be suitable, and they were offered water at frequent 

 intervals. They were weighed daily. They were handled with 

 great gentleness, and even the wildest soon ceased to show signs 

 of fear. Overnight they were kept in clean cages. 



EXPERIMENTAL 

 MONKEY 4 



Monkey 4 seemed to show in the sun the typical reaction of 

 a young, healthy Philippine monkey. Immediately below is a 

 brief account of the main happenings in its experience during 

 five months in the Manila sun. 



This was a strong, active, healthy, wild male, which we sur- 

 mised to be rather young. It weighed 1,528 grams when ob- 

 tained, but within a few days it lost 100 grams- It has 

 maintained practically constant weight ever since. We have not 

 been able to detect in this monkey any signs of sickness. It has 

 never suffered any significant injury. During the course of 

 the experiments it has become much tamer, 



A simple, wholesome diet, consisting of boiled white rice and 

 raw ripe banana, was chosen. Twenty-five grams of each food 

 for each kilogram of body weight were furnished the monkey 

 at about the same hour once each day. Slight temporary changes 

 in the diet from time to time did not seem to change the results. 



