211 
Table IL 
Discharge into the Atmosphere. 
Lbs. per 
square inch 
Effective 
Pressure 
ofl^ 
Sd 
og 
o 
Plain Tube 
^ Orifice. 
Conoidal 
1 W Orifice 
Inside. 
Conoidal 
O Orifice 
Inside. 
Conoidal 
O Orifice 
Outside. 
Conoidal 
0 Orifice 
Inside. 
Conoidal 
O Orifice 
Outside. 
Double 
H Conoidal 
Orifice. 
Coefficients 
O for 
Orifice. 
sec. 
sec. 
sec. 
sec. 
sec. 
sec. 
sec. 
sec. 
15 
16-0 
13*5 
14-0 
14*0 
14-0 
14*5 
14-5 
15*0 
•829 
13 
17*5 
14-5 
15*0 
15*0 
15*0 
16*5 
16-0 
16*0 
•829 
11 
19-5 
160 
16*5 
16-5 
16-5 
18*5 
18*0 
17*5 
•820 
9 
22-5 
18-0 
18*5 
18*5 
18-5 
20-5 
19*5 
19-0 
•818 
7 
26-0 
21*0 
21*5 
22.0 
21*5 
24*0 
21*5 
22*0 
•808 
5 
33*0 
26-0 
26*5 
27*5 
26-5 
30*0 
25*5 
27*0 
•788 
3 
51*0‘ 
39-0 
40*5 
42-5 
40*5 
47*0 
38*5 
42*5 
•765 
On comparing the times of discharge through the several 
orifices among themselves, and with those in Table I., a 
marked difference is observable in them. Thus the ratio of 
discharge through the tube orifice A and the orifice in a 
thin plate is greater than that for the same orifices in 
Table I., the coefficients for the highest and lowest pressures 
in this table being -935 and *904 respectively ; whereas the 
coefficients for the same orifices in Table II. are -829 and 
•765 respectively. Again, while there is little difference in 
the times of discharge from the tubular orifices among them- 
selves, a remarkable change occurs during the fall of pressure 
from 151bs. to 11b. when the discharge is made through C 
and D with the conoidal orifices outside the vessel. 
The discharge through D from 151bs. to ISlbs. is the same 
whether the conoidal orifice is inside or outside ; but in the 
latter position, as the pressure diminishes, the rate of dis- 
charge increases, till at the lowest pressure this increase 
amounts to 8*5 seconds, and exceeds the maximum discharge 
from the tube orifice A. A similar change is also noticeable 
in the rate of discharge through reversing the orifice C ; but 
as the change does not come on before the pressure is below 
