348  D.M. Balch on Orthite from Swampscot, Mass. 
orbit an ellipse. The path of the meteor cannot be carried 
much to the eastward so as to shorten its length, and thus di- 
minish the velocity. Its azimuth may be changed, several dee 
grees even, without great violence to the observations, but this 
will have little effect upon the heliocentric velocity. 
he meteor cannot reasonably be supposed to have ascended 
during the larger part of its course. On the other hand, to 
change it so as to make it describe a descending line would in- 
erease the heliocentric velocity. 
Any change then must be in the duration of the flight. If the 
body was moving about the sun in an elliptic orbit, and the line 
given above was its true path, the geocentric velocity could not 
be greater than about 14 miles a seeond, which would require 
16 or 18 seconds for the whole flight. This would moreover 
make no allowance for the resistance of the atmosphere. Though 
an elliptic orbit is very possible I can hardly think it probable. 
Yale College, March, 1862. ! 
Arr. XXXIII.—On Orthite from Swampscot, Mass.; by DAVID 
M. Baca, B.S. 
More than a year since, while examining the rocks at Swamp- 
scot Beach, near the Clifton House, I observed a mineral occur 
‘ing in small amorphous masses in quartz and red feldspar, 
which immediately attracted my attention by its peculiar lustre 
and appearance; this on examination has proved to be orthite 
almost identical with that from the Norway granite. 
The shore at Swampscot and for half a mile or so N.E. towards 
ph d extending 0 
feet backward, and, at the most, from 15 to 20 feet in height, to 
good 
the subject for this S 
The orthite is found almost always imbedded in — ma 
have obtained a few pieces from the feldspar, which forms * 
bulk of the veins; it occurs in black amorphous masses, 8° 
times surrounded with a reddish coating of sesquioxyds of 1707 
and cerium, when much exposed to the weather or the acti 
eir whole 
a 
ficiently to determine its name en spe er 
more carefully again this winter, and give below an outlin 
