June i, 1921 Some Fundamentals of Stable Ventilation 365 
first, at the rate recommended by King, and second, at the rate com¬ 
puted by the writers (Table XVII, columns 6 and 5, respectively). 
Table XIX .—Temperature in stable as compared with that outside 
Temperature of outside air. 
Temperature of air in stable. 
Corresponding to King’s figures for ventilation. 
Correspond¬ 
ing to 
air flow 
given in 
Table 
XVII, 
column 5. 
Cow. 
Horse. 
Swine. 
Sheep. 
All species. 
°F. 
°F. 
°F. 
°F. 
°F. 
°F. 
— 20 
15.6 
-0.4 
O. I 
-6. 7 
16.5 
— IO 
25.6 
9.6 
IO. I 
3-3 
26. 5 
O 
35-6 
19. 6 
20. I 
13-3 
36. 5 
IO 
45 - 6 
29. 6 
30. I 
23-3 
46- 5 
x 5 
50.6 
34-6 
35 -1 
28.3 
5*-5 
20 
55-6 
39 -& 
40. 1 
33-3 
56.5 
25 
60. 6 
44.6 
45 - 1 
38.3 
61.5 
30 
65.6 
49.6 
50. 1 
43-3 
66.5 
35 
70. 6 
54 '6 
55 - 1 
48-3 
7 i- 5 
This table is interesting in that it shows approximately the point at 
which the heat supplied by the animals becomes deficient for maintaining 
the proper temperature in the stable. Thus, when King’s standard of air 
flow is taken as the minimum, the heat supplied by cows appears to be¬ 
come deficient for maintaining what is believed to be the best stable 
temperature when the outside temperature is below 15 0 F. The heat 
supplied by horses, swine, and sheep appears to become deficient at a 
much higher outside temperature. When, however, the rate of air flow 
computed from the carbon-dioxid production is made the basis of the 
computation, the differences between the species disappear. 
MAXIMUM VENTILATION TO MAINTAIN A GIVEN TEMPERATURE 
difference 
Conversely, the same data may be used to compute the maximum 
rate of air flow compatible with the maintenance of a given temperature 
difference between the stable and the air outside—for example, a stable 
temperature of 50° F. in zero weather—since it is evident that if the air 
flow be reduced the temperature difference and consequently the efficiency 
of the animals to warm the stable will be increased, while if the ventila¬ 
tion be increased the contrary will be the case. To illustrate this point 
Table XX has been computed, showing what rate of air movement would 
be required if it were desired to maintain a temperature difference of 50° 
between the stable and the outside air. It should be noted that, as in 
Tables XVIII and XIX, these are maximum values, since no allowance 
is made for losses of heat through the stable walls. 
