OBSERVATIONS ON THE MAGNETIC DIP AND DECLINATION. 367 
at its base. Irom this point the house of the Hon. Levi Woodbury is about three hun- 
dred feet in a north-easterly direction. Latitude 43° 04/27’, N.; Longitude 70° 46' 36”, W 
Neepie No. 1. 
iMarked sat. edtinge Observation. Temperature Dip observed 
Ss L6is-9 11h. 18m., A.M. 80° 74° 57.15 
N 16 Lj, 49 y 79 74° 58'.28 
Dip, by thirty-two observations on needle No.1, . . . . . . 74° 55/2] 
NeEeEpLeE No. 2. 
Ss 16 Oh. 14m., P.M. 78° 74° 52'.08 
N 16 0 43 = 78 74° 52'.34 
Dip, by thirty-two observations on needle No.2, . . . . . . 74°52/.18 
Dip, by a mean of sixty-four observations on needles Nos.1 and 2,. . . . 74° 53'.7 
Weather clear and pleasant. <A fresh south-west wind. 
XXXIX. May 3d, 1844.—Portsmouth, New Hampshire. 
On Shapley’s Point, being the southern extremity of Shapley’s Island, four paces 
west of the trigonometrical station on this island. Latitude 43°04’ 10.5, N.; Longitude 
70° 44’ 48”, W. 
NEEDLE No. I. 
N 16 3h. 02m., P.M. 67° 74° 55'.48 
s 16 3 32 ¥ 66 74° 60'.31 
Dip, by thirty-two observations on needle No.1, . . . . . . 74° 57'.87 
NEEDLE No. 2. 
N 16 Ah. 02m., P.M. 66° 74° 59'.90 
Ss 16 4 382 _ 66 74° 577.15 
Dip, by thirty-two observations on needle No.2, . . . . . . 74° 58'.52 
Dip, by a mean of sixty-four observations on needles Nos.l and2,. . . . 74° 58/2 
Weather clear and pleasant. Strong south-west breeze. 
XL. May 4th, 1844.—Portsmouth, New Hampshire. 
On “One 'Tree Island,” a small island about one-fourth of an acre in area, opposite to 
Union Wharf. Latitude 43° 04’ 40”, N.; Longitude 70° 45’ 17’, W. 
Notn.—This is a very eligible position for magnetic observations, being very accessible from the city, and 
remote from any apparent cause of disturbance of the needle. 
NEEDLE No. 1. 
S 16 Oh. 50m., P.M. 59°. 74° 58.68 
N 16 1 “6 A 57 74° 56'.28 
Dip, by thirty-two observations on needle No.1, . . 9... . 74° 57.48 
Neepie No. 2. 
Ss 16 2h. Olm., P.M. 55° 74° 53’.68 
N 16 2 86 tt 56 74° 60'.87 
Dip, by thirty-two observations on needle No.2, . . . . . . 74° 57/.27 
Dip, by a mean of sixty-four observations on needles Nos. land 2, . . . 74° 57/.37 
VOL. IX.—96 
