No data were obtained in still, saturated air at 981° F., but in moving air under these conditions the following effects were noted (Table II): The body temperature of subject No. 1 rose to 102.3° after spending an hour in the test place. The body temperature of subject No. 2 rose from normal on the surface to 100° F. before going into the test place, due to a certain amount of leisurely walking on levels in still, nearly saturated air around 90° F. Body temperature rose from 100° to 101.3° F. after sitting still an hour in the 984° swiftly moving, saturated air, and continued to rise even after the subject left the hot location. His pulse rate rose from 88 at the surface before going underground to 104 after walking around underground, as described above; and after sitting the hour in the moving 984° saturated air it was 158. This swiftly moving (500 to 800 feet per minute) saturated air at 98° made subject No. 2 feel decidedly dizzy upon even slight exertion or emotion, his skin felt hot, perspiration was very profuse (saturating clothing and nearly filling shoes), and though very strong physically he felt very weak after the test, and said it was far more oppressive than the experiences in moving, saturated air at 920, 95°, or 96°, but was not as bad as still, saturated air at 95°.

The data for this test on subject No. 4 in the same velocity of air show that the body temperature went to 103° and the pulse rate to 183, these high readings being due probably to the fact that subject No. 4 had done some work setting the fan before entering on the test. Subject No. 4 also had hot skin, some dizziness, weakness, and trembling, and had clothing saturated with perspiration, his shoes being nearly full of sweat. He felt that the test was much more severe than in moying, saturated air at 95° or 96°, but not as bad as still air at 95° when saturated.

Data on subject No. 5 sitting still an hour in the 984° saturated air, with velocity about 300 linear feet per minute, show that he had essentially the same unfavorable symptoms as subjects Nos. 2 and 4, his body temperature going to 101.9° and his pulse rate to 146. He also felt dizzy, weak, and had a "heaviness in the head." He pronounced it a trying experience, stating that he believed it would be impossible for him to work under such conditions.

TABLE III B.-Effects of resting one hour in moving air at 100° wet bulb, 100° dry bulb (100 per cent relative humidity).

(No. 5 in velocity of 650-700 feet; Nos. 4 and 5,
700-800 feet; No. 2, 200-300 feet.

No. 1 was puffing and visibly in distress to a
slight extent at 10; No. 5 was fine; No. 2
O. K., but hot; same for No. 4. All sweating
heavily; sitting upright in the hot moving
air; No. 4 soon felt skin very hot; air "feeling
like that from a furnace."

At 10.12 No. 1 dizzy and looking distressed;
quit at end of 30 minutes, or at 10.18. No. 4
started to breathe hard at 10.18; No. 5 slightly
dizzy and hot. No. 2's head "felt big" at
10.20; quit at 10.28. No. 4 quit at 10.23 on
account of difficulty in breathing. No. 5
quit at 10.32 on account of temperature of
102°. No. 1's arms not sweating well at 10.18;
he had chilly sensations about spine and was
weak in legs as he walked out; had tempera-
ture of 103 5 minutes after going out of hot
location. No. 4's temperature was 102.4°
about 3 minutes after coming out; he had
difficulty in breathing for at least 10 minutes
after coming out, and his pulse was 170; he
was weak, dizzy, and puffing for 15 minutes.
No. 2 came out after 40 minutes, temperature
5 minutes afterwards was 102.3°, taken in
moving air, same as No. 1. No. 2 was weak
and dizzy, especially on standing up. No. 5
came out after 43 minutes in hot air, with
temperature of 102°; could have stayed 5

In the saturated air at 100° (Table III B), subject No. 2 sat at a point where the air had a velocity of 200 to 300 linear feet per minute, subject No. 4 in velocity of 700 to 800 feet, and subjeet No. 5 in velocity of 650 to 700 feet per minute. No one was able to remain the full hour in this moving, saturated air at 100°, subject No. 2 being compelled to leave after sitting still for 45 minutes, subject No. 4 leaving after 40 minutes, and subject No. 5 leaving after 49 minutes. All subjects began to feel ill in less than 30 minutes in this swiftly-moving, saturated air at 100°; all perspired excessively and felt dizzy and weak. All were convinced that to try to remain the full hour might result in collapse, and were united in the conviction that while it was advantageous to give motion to saturated air below 98° F., movement was a decided disadvantage to saturated air above 98° F. It will be noted that pulse rate and body temperature apparently did not have time to go to higher limits, though all subjects had body temperature over 102° F. and an increase in pulse rate of 40 per cent or over.

SUMMARY.

A. Remaining at rest in saturated air at 911° F. for one hour,
With no air movement caused-

1. An increase in body temperature;

2. A moderate increase in pulse rate;

3. Profuse sweating;

4. After effects of dizziness and weakness.

With air movement caused

1. Slight or no increase in body temperature;

2. Slight increase in pulse rate;

3. Slight perspiration;

4. No after effects;

5. No ill effects at any time; but the noise of the fan was
annoying.

B. Remaining at rest in saturated air at 95° for one hour,
With no air movement caused—

1. An increase in body temperature;

2. A marked increase in pulse rate;

3. Very profuse sweating, clothing being saturated with perspiration and sweat in shoes of all subjects;

4. Dizziness on movement, and increase in depth and rate of respiration (puffing somewhat on slight movement); chilly sensations in some subjects.

With air movement (250 to 600 linear feet per minute) caused1. Slight or no rise in body temperature;

2. Slight or no rise in pulse rate;

3. Profuse sweating, but not sufficient to wet all clothing; 4. No untoward symptoms in subjects other than profuse sweating.

C. Remaining at rest in saturated air at 96°, still and moving, caused the subjects to experience symptoms practically the same as those felt in still or moving saturated air, repectively, at 95° F. D. Remaining at rest in saturated air at 981° F. for one hour, With air movement caused

1. An increase in body temperature;

2. An increase in pulse rate (in one case to 183);

3. Very profuse sweating, clothing being saturated (sweat could be poured from shoes);

4. Dizziness on movement. All felt that little work could be done at this temperature and that the conditions were much worse than in moving saturated air at 95°, but not as bad as moving saturated air at 100° F.

E. Remaining at rest in saturated air at 100° F.,

With no air movement caused

1. A marked rise in body temperature, which reached 102.3° F.;

2. A marked rise in pulse rate, varying in different subjects from 152 to more than 175;

3. Profuse sweating, the shoes being partly filled with perspiration;

4. Early appearance of dizziness, weakness, and persistence of symptoms for about one hour after test. The test was very trying.

With air movement (200 to 800 linear feet per minute) causedAll the above symptoms, and no subject remained a full hour.

The untoward effects upon man of almost saturated air with temperature above 90° F. and below 98° F. are much less when the air is moving than when it is still. Further, the output or work that can be done is greater when the air is moving than when it is still, with the above temperature and humidity.

No beneficial effects were found by moving saturated air at 98.6°. or 100° F., even at high velocities; and there was apparently some disadvantage.

BIRTHS, DEATHS, AND INFANT MORTALITY, 1921 AND 1922.

PROVISIONAL FIGURES FOR 1922 AND RATES FOR 1921 AND 1922 IN THE BIRTH REGISTRATION AREA OF THE UNITED STATES,

The Bureau of the Census, Department of Commerce, has issued a pamphlet entitled "Summary of Provisional Birth and Mortality Figures, 1922," from which the table printed below is taken. Similar data are given in the pamphlet for 547 cities in the United States having more than 10,000 population.