AND THE INTENSITY OF MAGNETICAL FORCE. 320 
Patterson, at the bottom of Garret Rock, and near to the Morris Canal; June 10, 1844, 
Duration | Calculated Total intensity 
Dip. No. of | Epoch of commencing of 500 = |Tempe-| duration Square of the Horizontal |that at Cincin- 
Needle, Vibrations, Vibrations.) rature. at 60°. preceding. intensity./nati being 1000. 
; | 
72° 17'24"| 4 | 1h.13m.00s.8 P|1171.60,82°00 |1169.92 1368712.8064 900.88 | 992.64 
Substratum, sandstone, just below its junction with the superimposed trap rock. The 
trap of this vicinity is compact, and of a dark colour, entirely destitute of that granular 
feldspathic structure so apparent in that of Bergen hill. 
Patterson, at Mr. R. Colt’s Garden, nearly in the centre of the valley in which the town stands. 
72°58'06"| 4 | 3h.21m.03s.6 P[1192.0 | 77° |1190.7 |1417766.49 [869.71 | 995.72 
This locality, similar to the “ orchard,” at Fort Lee, may be considered, probably, free 
from any immediate local attractions, as it is upon a deep substratum of silicious sand, 
and that again superimposed on sandstone, with no appearance of trappean rocks within 
halfa mile. The distance from Garret Rock is about three-fourths of a mile, in a course 
a little east of north. 
The following diagram shows the curves of dip and intensity in traversing Patterson 
and Garret Rock from north to south. 
my RS <I 
ea NO axe . 
5 5 S i 8: ls Seals schol een 
mn er 
il Top »). | 16 | Ce ae! 
2 > Pie, ‘ 
y | SR Diy i 
; merrers Rock. ess = 
ae tt 
ii & Bottom ? of G@ Rock | 
ae ia © 
\ ea 
fi is Gare one Z 
} i 
Ke) © a) Lag bad bs ba iS my 
ig is iS 8 S S) 3 S S aT pt ert fey 
3 Ky 3 iS is v g BS & 2 Intensity 
REMARKS ON LOCAL ATTRACTIONS. 
In the three localities above-named, Snake Hill, Fort Lee, and Patterson, the geology 
and topography are similar, presenting trappean elevations of moderate height, but 
having mural or precipitous sides. In the two latter, the trappean mass is superimposed 
on sandstone, and probably in the first also, but at a depth as yet unexplored. In all of 
these localities the magnetical elements exhibit the same general phenomena, viz., at the 
base of the precipice both the dip and the intensity are diminished, but, at the summit, 
