ATMOSPHERE AND THE ACOUSTIC EFFICIENCY OF FOG-SIGNAL MACHINERY. 273 
Father Point Meteorological Observations, September 5. 
Barometer, 29 - 97. Air temperature : dry bulb, 47° F.; wet bulb, 44° F. 
Wind: steady; 3-4 p.m., Telocity 5 miles per hour from W.; 4-5 p.m., Telocity 4 miles per hour from W.; 5-6 p.m., 
velocity 4 miles per hour from W. Weather clear. Sky unclouded during observations. 
Phonometer Readings. 
Line VIII. . September 5. 
Position 
No. 
Phono¬ 
meter. 
Position 
No. 
Phono¬ 
meter. 
Position 
No. 
Phono¬ 
meter. 
Position 
No. 
Phono¬ 
meter. 
Position 
No. 
Phono¬ 
meter. 
1 
(10 
•5) 
17 
1 
7 
33 
1 
*7 
49 
0 
•6 
65 
5-8 
2 
(6 
0 ) 
18 
1 
i 
34 
1 
•o 
50 
. 0 
■9 
66 
5-9 
3 
8 
•4 
19 
1 
6 
35 
1 
•1 
51 
1 
•o 
67 
6 '5 
4 
6 
•o 
20 
1 
6 
36 
1 
•2 
52 
1 
•4 
68 
6'3 
5 
7 
•8 
21 
1 
4 
37 
0 
■8 
53 
1 
•6 
69 
6-0 
6 
4 
’7 
22 
1 
4 
38 
0 
•8 
54 
2 
•4 
70 
6-0 
7 
3 
•o 
23 
2 
6 
39 
0 
•4 
55 
2 
•6 
71 
6-8 
8 
2 
'7 
24 
2 
5 
40 
0 
•2 
56 
3 
•3 
72 
9 3 
9 
3 
■5 
25 
3 
0 
41 
0 
•3 
57 
3 
■3 
73 
9 0 
10 
2 
26 
2 
7 
42 
0 
'7 
58 
3 
•6 
74 
9-6 
11 
i 
•6 
27 
3 
3 
43 
0 
•4 
59 
4 
•3 
75 
10 -o 
12 
0 
•9 
28 
2 
3 
44 
0 
•3 
60 
3 
•6 
76 
12-5 
13 
1 
•3 
29 
2 
3 
45 
0 
•4 
61 
4 
•4 
14 
1 
•4 
30 
i 
7 
46 
0 
‘5 
62 
5 
’2 
15 
1 
•1 
31 
i 
7 
47 
0 
■3 
63 
4 
•8 
16 
1 
1 
32 
i 
9 
48 
0 
•3 
64 
5 
•8 
Remark.';. 
Readings plotted on Chart 2. Wind, 5 miles per hour from W. Sea smooth. 
1. Time, 4.15 p.m. 1-2. Resonator at position 0 ; readings, 3'5 and 2'0; entries calculated for position 8 from observation 4. 
Line 1 of Table 1. 44. Time, 5.10 p.m., turned back along same line. 
Line III. 
September 5. 
Position 
.No. 
Phono¬ 
meter. 
Position 
No. 
Phono¬ 
meter. 
i Position 
No. 
Phono¬ 
meter. 
Position 
No. 
Phono¬ 
meter. 
Position 
No. 
Phono¬ 
meter. 
i 
5 '5 
7 
3 4 
13 
2 5 
19 
2 3 
25 
4 3 
2 
5 -0 
8 
3 5 
14 
2 3 
20 
3 0 
26 
46 
3 
4 6 
9 
2 -2 
15 
2-8 
21 
2 6 
4 
4 5 
10 
3 1 
16 
1 -9 
22 
27 
5 
2 6 
11 
2-3 
17 
1 -9 
23 
3 0 
6 
2 2 
12 
2 -4 
IS 
2-3 
24 
3'6 
Remarks. 
Readings plotted on Chart 2. Wind, 4 miles per hour from W. Sea smooth. 
13. Turned back along same line. 26. Boat grounded on beach. 
Control station .—Mean of two readings, 33. 
Mean air-pressure operating diaphone at conclusion of observations, 18 '3 lbs. per sq. inch above atmospheric. 
