386 
MESSRS. R. H. FOWLER, E. G. GALLOP, C. N. H. LOCK AND H. W. RICHMOND: 
Table YIIIb. (continued). 
Elevation 30 degrees. 
1 . 
2. 
3. 
4. 
5. 
6. 
7. 
0 
1-945 
0-00056 
0 
0 
• ' 
1 
2-55 
0-00086 
2 
3-21 
0-00122 
0-00080 
1-1 
4 
4-79 
0-00234 
0-00174 
4-1 
6 
8-43 
0-00368 
0-00351 
9-5 
8 
9-11 
0-00581 
0-00655 
19-2 
0 7 
10 
11-16 
0-00785 
0-01022 
34-4 
12 
14-01 
0-01063 
0-01417 
55-3 
0 15 
14 
15-75 
0-01276 
0-01828 
82-0 
16 
17-48 
0-01495 
0-0225 
114-3 
0 24 
18 
18-85 
0-01671 
0-0269 
152-0 
20 
19-92 
0-01810 
0-0316 
195-0 
0 35 
24 
0-0191 
0-0418 
297 
0 46 
28 
0-0174 
0-0525 
419 
0 59 
32 
0-0143 
0-0629 
557 
1 11 
36 
o-ono 
0-0729 
708 
1 23 
Table IX.—Comparison of Calculated Drift with Observations of April-May and 
February, 1918. 
The azimuth of the shell at time t (in minutes of angle) = At. 
Elevation 50 degrees. 
Observations of April-May. 
Rifling 1/30. 
Mean observed 
time. 
, 
Mean observed r , , , , , , 
^ Calculated A. 
10-9 
1-46 1-27 
23-9 
2-24 2-29 
33-3 
2-89 2-85 
41-3 
3-16 i 3-36 
Rifling 1/40. 
Mean observed 
time. 
Mean observed 
A. 
Calculated A. 
10-2 
1-18 
0-90 
22-9 " 1-30 
1-66 
31-0 
1-95 
2-10 
39-1 
2-00 
2-44 
