The Sun.
London, England, 1841-03-18 00:00:00

of several intermediate points of the river St. Croix on
its expanded lake surface, have been accurately aseer-

tained.
" Another officer was at the same time charged with
tracing a line of levels from the base of the same MOnU-
meat, along the due-north line, as marked by the Com-
missioner, by which it is intended that every undulation,
with the absolute heights above the plane of mean low
water at Calais, shall be shown along the whole extent
of that line.
" At Park's Hill, distant nearly twelve miles from
the monument, a second station for astronomical obser-
vations was established, and a camp suitable for that
purpose was formed. On the 26th of October, whilst oc-
cupied in completing the promuls;ation of the meridian
line to that point, and in estnbi.ishing a camp there, the
party was visited by a snow-storm, which covered the
ground to a depth of four inches in the course of six
hours. This was succeeded by six days of dark stormy
weather, which entirely interrupted ail progress, and
terminated by a ran with a change to a milder tem-
perature, which cleared away the snow. During this
untoward (vent the parties made themselves as comfort-
able as practicable in their tents, and were occupied
in computing many of the astronomical and offer ob-
servations previously made.
" On the 2d of November the weather became clear,
and the necessary astronomical observations were ini-
medietely commenced at Park's Hill. From this ele-
vated point the first station could be distinctly seen by
means of small heliotropes during the day, aed bright
lights erected upon it at night. Its direction, with that
of several intermediate stations due south of Park's
Hill, was verified by a new series of transit observations
upon high and low stars, both north and south of the
zenith. By the same means the line was prolonged to
the roith.
" In one week after commencing the observations at
Park's Hill the weather became again unfavourable ;
the sky was so constantly overcast as to preclude all
astronomical observations, and the atmosphere so thick
as to prevent a view to the north, which would not
permit new stations t.) be estallshed with suffic:ent
accuracy in that direction. UriwTing to quit the
Lbl while there was a prospect of the weather be-
coming sufficiently favourable for the party to reach
the latitude of Mars Hai, or even proceed beyond
it, it was determined that some of the patty should
continue in the tents, and there occupy themselves
%vita such calculations as ought to be made before
quitting the Brad. The officers charged with the line of
levels and with the reeonnoissgnee in advance for the
selection of new positions for stations, continued their
' labours in their field, notwithstanding they m ere, fre-
quently exposed to slight rain and snow storms, as
these portions of the work could go on without a
clear sky.
" On tie 13 h of November a severe snow storm oc-
curred, which in a single night and a portion of the fol-
lowing morning coveted the surface of the wbele coun-
try,-andthe roofs of the tents, to a depth of sixteen
inches. Tire northern extremity of the avenue which
Lad been cleared by the surveyors of 1817 wag
now reached, aid in addition to the young growth
which had sprung up since that period upon the
previous part of the line, several miles had been
cleared through the dense forest of heavy timber, in
order to proceed with the line of levels, which had
reached nearly the Meduxnakeng. • The depth of snow
now on the ground rendered it impracticable to con-
tinue the levelling with tae requisite accuracy any far-

titer ; and that part of the work was accordingly sus-
pended for the season. The thermometer bad long
since assumed a range extending during the night, and
frequently during a great portion of the day, to many
degrees below the frezzing point.
" The highlands bordering on the Aroostock, distant
-40 miles to the north of the party, were distinctly seen
from al elevated position, whenever the atmosphere
was clear ; and a brig extent of intermediate ecuntry, of
inferior elevation to the position then occupied, pre-
sented itself to the view, with the two peaks of Mars
Hid rising abruptly above the geaeral surface which
surrounded the:r base. The eastern extremity of the
base of the e tsternmost peak was neatly two degrees of
an acre, or nine-tenths of a mile in space to the west of
the line as it passed the same latitude.
"To erect stations opposite to the base of Mars
HiP, and upon the heights of the Aroostock, in order
to obtaic exact comparisons with the old line at these
points, were considered objects of so much importance,
as to determine the Commissioner to continue the ope-
rations in the field to the latest practicable period, in
hopes of accomplishing these ends.

Oa the 18. h (ley Of November the party suece:2ded

in erecting a sta'ion opposite Mars Hill, and very near
the meridian line. It was thus proved that the line
woul I pass from nine tenths of a mil to one mile east of
the eastern extremity of the base of the north-eastern-
most peak of Mars Hilt.
" On the 304 r of November a series of signals was
commenced to be interchanged at night betwe?.n the
position of the transit instrument on Park's Hill, and
the highlands of the Aroostock. These were continued
at intervals, whenever the weather was sufficiently clear,
until, by successive approximotions, a station was, on
the 9th of . December, est iblished on the heights one
mile south of that river, and on the meridian line. The
point thus reached is more than 50 miles from the
monument at the source of the Saint Croix, as ascer-
tained from the land surveys made under the authority
of the S ate of Maine and Massachusetts. The men-
, surements of the party could not be extended b this
last point, owing to the depth of the snow, which lay
upon the ground since the middle of November ; but
the distance derived from the land surveys must be a
very near approximation to the truth. A permanent
station was erected at the position established on tle
Aroostock heights, and a measurement made from it.
due west, to the experimental or explorng line of 1817,
by which the party found itself 2,400 feet to the east of
that line.

" Between the Ist and 15th of December, the obser-
vations were carried on almost exclusively during the
night, and frequently with the thermometer from 0 to
10 and 12 degrees below that point by Fahrenheit's
scale. Although frequently exposed to this tempera-
ture in the performance of tleir duties in the open air
at night, and to within a few degrees of that tempera-
ture during the hours of sloop, with no other protection
than the tent and camp beds commonly used in the
army, the whole party, both officers and men, enjoyed
excellent health.

" During the day the tents in which the astronomi-
cal computations were carrie I on, were rendered quite
comfortable by means of small stoves; but at night the
fire would become extinguished, and the temperature
reduced to within a few degrees of that of the outward
air. Within the observatory tent the comfort of a fire
could not be indulged in, in consequence of the too
great liability to produce serious errors of observation
by the smoke passing the field of the telescope. Tee
astronomical observations were therefore always made
in the open air, or in a tent open to the heavens at top
during the hours of observation, and without a fli e.
"Oa the 16th of December the tents were struck,
and this patty retired from the field for the season,
there being ti.en more than two feet of snow on the
ground. To the unremitting zeal, amidst sevore ex-
posures, and to the scientific snd practical attainments
of the officers, both civil and military, who served
under the orders of the Commissioners on this duty, la;
acknowledges himself in a great measure indebted for
the progress that he was enabled to make, notwithstand-
ing the many difficulties encountered.
" Observations were made, during portions of three
lunations of the transit of the moou'a bright Hail), and
of such tabulated stars as differed but little in right
ascension and declination from the moon, in order to
obtain additional data to those furnished by chrono-
metrical comparisons with tl-e meridian of Baston, for
computing the loncitude of this meridian line.

. . -
" At the first station, 4,578 feet not CI of the mann-
ment, and also at the Parles Hill station, the dip of the
magnetic needle was ascertained by a series of observa-
tions ; in the one case upon two, and in the other upon
three separate needles. The horizor t J declination was
also ascertained, at both these stations, 1.1 a full set of
observations upon sin different needlts.
The details of these, and of all the aitronomical
observations alluded to, will ha prepAred as soon as
practicable for the use of tl.e Commission. should
they be required. To his Excellency Major-General
Sir John Harvey, K.C.8., Lieut.-Governor of the
province of New Brunswick, Major Graham ac-
knowledged i
himselfgreatly indebted for having in the
most ob g manner extended to him every facility
within his power for prosecuting the examinations.
From Mr. Connell, of Woodstock, a member of the
Colonial Parliament, and from Lieut.-Colonel M‘Laugb-.
lin, the British land-azeot, very kind attentions were
received.

" Majqr Graham has also great pleasure in acknow.
of the Eastern Department ; Colonel Pierce, ledginm' his obligatiot:s to General Eustis, Commandant
command-
ing the garrison at Houlton, and to his officers; and
also to M.,jor Ripley, of the Ordnance Department,
corrinvinding the arsenal at Augusta, for the prompt
and obliging manner in which they supplied many arti-
cles usetul in the prosecution of the !hours of his party.
was ernetrautdrnin,:tiat
binesetnrutmolennet,wi
tit3h
twhheicchottnhme
inisseiorild) inbny linethe
Hon. W. A. Deer, PresP.eat of Columbia College ,
New York, and the_ Cornruissioncrs feel bound to
return their acknowle;lgoi,:nts for the liberality with
which the use of this astronor&cal instrumeat
granted,
to have . aid perhaps impossible, procured one as well
at a time when it would 1,
Commissioners.
ave leen difficult,
" All of which is respectfully submitted.
„ JAMES RE N WICK
JAMES D. GRAHAM
A. TALCOTT -
the object.
of
i, Hon.
suitcd to
John Fors. th, Secretary State."

Sir Robcrt and Lady Peel entertained the Earl
and Countess ofJersey, Earl and Countess of Charlevitle
Earl awl C,'nentes. cf GI f:s11, Earl cf Aberdeen, Lad;
zlarall f.(pd Cunt Everlins;
1.11 Alut • ihrh
w,,,uelei, Mr. tiud dLailitte EgLi
a ce'ect patty to dinner last evening:, at their 111811,Ln in
Whitehall gardens.