AND THE INTENSITY OF MAGNETICAL FORCE. 303 
58. Boston, Latitude 42° 22’, N.; Longitude 70° 59’, W.; May 2, 1843. 
tego Duration Calculated ‘Total intensity, 
Dip. No. of | Epoch of commencing| of 500 /Tempe-} duration Square ofthe | Horizontal/Total intensity,/that at Cincin- 
Needle, Vibrations. Vibrations. rature. at 60°. preceding. intensity.|Hor. being 1000,/nati being 1000. 
74°05'40" 1 6h.04m.038.2 AJL712.4 | 55° |1713.43/2935842.2649 807.39 
2 6 45 04 4 {1691.6 | 51 5 1693.68/2868551.9424'805.09 
3 7 53 10 1377.2 | 54  |1877.58)1897726.6504/804.83 
4 |12 13 O01 2P)1236.4 | 61 /1236.82)1528487.1424/806.47 
5 |12 44 08 6 |1504.4 | 54 |1505.03)2265115.3009/805,.21 
6 1 15 00 1500.0 | 54 |1500.7912252370.6241/805.36 
Mean, |805.72 2940.02 984.47 
Locality, in the garden of the Coolidge House, Bowdoin square. Geology, deep 
diluvium. 
59. Cambridge Observatory, May 4, 1842. 
74°14/52"| 1 |11h.42m.038.6 A1714. 48° |1716.5 |2946872.25 \804.50 | 
12 20 00 P1694.8 | 48 1697.7 2882185.29 801.28 
2 00 04 4 {1378.4 | 50 {1379.2 |1902192.64 [802.94 
33 04 4 [1234.8 | 50 [1235.6 |1526707.86 (807.49 
38 05 O04 4 (1505.6 | 51 5 1506.5 2269572.25 (803.63 
3 43 04 8 (1500.8 | 52 51501.8 12255403.24 804.28 | 
Mean,/804.02 | 2961.64 | 
ams ww 
rw) 
991.71 
In the Magnetical Observatory of Mr. Bond. Deep diluvium, superimposed on 
gneisse rocks. (?) 
60. Bristol, Pennsylvania, Latitude 40° 06’, N.; Longitude 74° 47’, W.; May 13, 1843. 
~~ “79°95'20"| 1 | Th. 7m.00s.2 P\1634.4 | 65° [1633.4 |2667995.56 [888.45 | 2941.56 | 984.99 
In the middle of Professor Vanuxem’s garden. Diluvium of clay, sand, and gravel, 
superimposed on primitive rocks. 
61. Philadelphia, Magnetical Observatory, May 15, 1842. 
1h.52m.048.8 P}1608.8 | 66° )1608.03/2585760.4809|916.70 
72° O1' 1 
2 2 36 59 6 {1685.2 | 56 5 1586.01/2515396, 918,13 
3 3 24 02 1290.4 | 52 5/1291.00/1666681. 916.40 | 
4 8 55 00 4 {1156.4 | 52 |1157.00)1338649. 920.83 
5 4 25 00 0 |1409.3 | 58 1410.30|1988946,09 917,02 
6 5 00 58 8 (1404.4 | 52 5)1405.30)1974868.09 (918.02 
Mean,/917.85 2972.88 995.48 
At the Observatory, near the Girard College. Rain commenced about the close of 
the observations. ‘There is a very close coincidence of the above observations and those 
made in March, of the preceding year, both in the details and in the mean results. The 
horizontal intensity of 1841 was 917.84 and 917.11, and, as above, in 1842, 917.85. 
VI. SERIES, 1843, CINCINNATI, (OHIO,) TO MICHIGAN, AND WISKONSIN, LAKE SUPERIOR. 
63. Cincinnati, August 21, 1843. 
1109,52)1231034.6304)1001.33 
1351.16 1825633.8456, 999.05 
1345,55|1810504.8025 1001.91 
Mean,|1000.76| 2986.98 
70°25'30% 4 |11h.17m.00s. A\L110.8 | 74° 
11 48 08 6 [1352.8 | 75 
12 31 00 0 P|1347.6 | 75 5 
} 
| 
an 
— 
| 
1000.20 
VOL. IxX.—80 
Sa 
