perature at the time of starting the test and then indicating the elevation during the stay in the test place by degrees above zero. The time is calculated in minutes, beginning with zero as the time of entering the test place. The solid lines on the graph represent the air temperatures without any air movement; the dotted lines indicate those with air movement. A similar graph made for the other subjects would show practically the same general results, so that the one representing the effects on the temperature of subject No. 5 may be considered fairly typical. EFFECT WITHOUT AIR MOVEMENT. Still saturated air at 911° F. caused the following symptoms in a subject: (1) A definite rise in body temperature; (2) moderate increase in pulse rate (18); (3) profuse sweating and feeling of weakness. The after effects were dizziness and weakness. Although subject No. 5 was the least readily affected of the three (2, 4, and 5), Figure 1 shows that there was a decided increase in his FIG. 1.-Effect of high temperatures and humidities on a subject in still and moving air. body temperature in the still, saturated air-at the close of the experiment, the rise above the entrance temperature being as follows: At 95° there was an increase of 1.4°; at 96° an increase of 2.3°, and at 100° an increase of 3.4°. The effect of the still, saturated air on the pulse rate was similar to that on the temperature. The rate of increase at 95° and 96° was practically the same, although the rate at the end of the test in still, saturated air was slightly higher at 95° temperature than at 96°, probably due to slightly more exertion by the subject during the 95° test than during the 96° test. The 100° still, saturated air increased the pulse rate very rapidly, the rate being 20 beats above that at 95° and 96° at the end of the test, or a total increase of 74 beats above normal. While sitting approximately an hour in still, saturated air, with temperature at 95° (Table I A), all the subjects were decidedly distressed, the body temperature going to 101.4° with subject No. 5, to 101.5° with subject No. 2, to 102.5° with subject No. 1, and to 102.5° with subject No. 4, the two latter being somewhat adversely affected by having exerted a little more effort than Nos. 2 and 5 (No. 1 in taking the readings and No. 4 in walking and climbing previous to undergoing the test). TABLE I A.-Effects of resting one hour in still air at 95° wet bulb, 95° dry bulb (100 per cent relative humidity). 96 All felt well; all had slept well, and apparently 99. 8 110 Spent from 9 to 10 a. m. trying to find a place While the subjects sat still for about an hour in this hot, humid, stagnant air the pulse rate increased from 104 to 158, or 54 beats for subject No. 2; from 144 to 170, or 26 beats for subject No. 4; and from 110 to 156, or 46 beats for subject No. 5. All subjects perspired very profusely, their clothing being thoroughly saturated and their shoes being partly filled with sweat; they were weak and dizzy, and all "panted" or "puffed" upon making the slightest effort. Subject No. 4 had acute soreness of the chest or lungs which did not disappear until about 10 hours after leaving the hot location. The resultant effects of sitting for an hour in the hot, humid air at 96° F. (Table II A) without air movement and doing no work other than occasional taking of body temperature or of temperature of the surrounding air, essentially checked those in still, saturated air at 95°; and all who underwent the hour test felt that it was a difficult experience. |