370 OBSERVATIONS ON THE MAGNETIC DIP AND DECLINATION. 
NEEDLE No. 2. 
Polarity of No of Time of 
Marked end. Readings. Observation. ‘Temperature. Dip observed. 
S 16 9h. O9m., A.M. 86°.5 71° 36'.12 
N 16 9°42 +8 88 71° 42'.81 
Dip, by thirty-two observations on needle No.2, . . . . . . 71° 89'.46 
Dip, by a mean of sixty-four observations on needles Nos. 1 and Qpris oor) ti TER BOes 
Weather clear and pleasant. 
[ obtained, for the dip at this station, by sixty-four observations on the same needles, 
and with the same apparatus in all respects, on June 11th, 1841, 71° 38°87. See No. 
XVIL., page 356. 
Here again, at another station within the same city, the increase of dip, during a 
lapse of three years and thirty-six days, seems only to have amounted to two-thirds of a 
minute. No circumstance attending the observations nor change of local circumstance 
as respects the station, since the first observations were made, could be perceived, that 
could affect the dip. 
XLV. 1844, July 22d,—City of New York. 
Centre of Washington Square. 
Neepue No. 1. 
N 16 6h. Olm., A.M. 67° 2° 29'.62 
Ss 16 Teeke 71 72° 32/34 
Dip, by thirty-two observations on needle No.1, . . . . . . 72° 30'.98 
Nezp.e No. 2. 
N 16 8h. 17m., A.M. 74° 72° 29' (75 
Ss 16 9 15 % 77 5 72° 23'.B4 
Dip, by thirty-two observations on needle No.2... . OG? Sere 
Dip, by a mean of sixty-four observations on needles Nos. 1 ana’ ott. fe 28.88 
Weather clear and dry. A very gentle breeze from the west. 
The length of time occupied in these observations was owing to interruptions from 
idle spectators. Care was taken not to read the needles whilst any one was near enough 
to them to affect them, in case there was metal about his person, such as knives, keys, &c. 
XLVI. 1844, August 5th.—Forks of the Kennebec, Maine. 
Latitude of point of observation 45° 20’ 03”, N.; Longitude 69° 58’ 16”, W. 
NEEDLE No. 1. 
Ss 16 6h. 32m., P.M. 67° 76°: 23' 48 
N 16 FOG u 61 .5 716° 22' 778 
Dip, by thirty-two observations on needle No.1, ... ..- « « 76° 23/28 
NEEDLE No. 2. 
Ss 16 Th. 33m. P.M. 58° 76° 22'.94 , 
N 16 8 00 Me 55 .b 76° 25'.40 
Dip, by thirty-two observations on needle No.2, . . . . >a. ame a. 
Dip, by a mean of sixty-four observations on needles Nos, 1 lh errr Pie! oft’ Br 
