'Transactions of the Bombay Geographical Society, from September 1850 to June 1852. Edited by the Secretary. Volume X.' [‎3] (22/458)

11163 "kea the,
1 ^ant,
n ^ er > N.
im P°«blef 0 ,
,dthe ff«»5 i
'“■OBial siunij
,rs ^ttcr mu^t
16 rei »arb oi,
^ontheEd^
l wwppteh en .
1 subject of tt e
n in circular,
3 issued, they
w as to the
l til the Socie-
-he balance in
'•j to be drawn
ie money was
ety’s accounts
it of the Ross
the Society:
sum sufficient
epared by Mr,
as a contribu-
publication—
d to write to
icted howto
i known; The
lid not appear
•
,ve compicte<i
by what ship
5 cut, cannot
jyany °PP or “
? et heard any-
-mpiesometer
i 0 ard, ^ th 8
jr , save ^nt
■the Ane^
uuld fear 111111
Con3M« rsb,e
EXPERIMENTS ON THE ANEROID,
iii
altitude. In all I have tried I found them agree pretty well down to 28 inches : below
this they get irregular and stop at about 27 inches. The moment I have notice of the
shipment of the instruments I shall let you know.
We remain, yours faithfully,
John Adie,
Alex. Adie & Son.
Edinburgh, 19th July 1850.
Dr. Buist, Secretary to the Bombay Geographical Society, Bombay.
In compliance with my intimation in May, when the account of the experiments on the
Aneroid in the Annual Report of the Society was laid before you, of trying a series of
experiments with the Aneroid at altitudes exceeding 1000 feet, the level at which it had
been formerly tried, I took three instruments with mo to Poona in the end of July.
Two of these belonged to Mr Treacher, one to the Society, this last being sadly out of
order: the cause of error was not observed at the time—*it arose from the slackening of
some of the screws, since tightened.
The results were the following—the Standard Barometers employed were Nos. 1 and
2, two of the finest sent out by Mr Adie—the way they kept together was quite admirable.
The Mountain Sympiesometer referred to was a very elegant instrument procured for
Colonel Campbell, whose indications were also very accurate, and in most perfect harmony
with those of the other instruments.
On comparing the instruments at Sewree, about seventy feet above the level of the sea,
they stood on the 22nd July at 10 a. m., as under, the thermometer being 84°, the correc
tion for temperature of the barometer here applied T49—the Standard at the Observatory
at this date was 29*667, the instrument being thirty-two feet above the level of the sea.
Barometers. Mountain. Aneroids.
, ——-^Sympiesometer.,——— .^
I. II. 5821 5822 2244
29.676 29.662 29*750 29*765 29*790 29*780
The following were the readings of the instruments respectively at Poona at 10 a „ m. on
the 27th—.the Observatory Standard had betwixt these two dates sunk from 29*667 to
29*587—or by 00.080:—
Temperature at Poona 76°, Barometer corrected.
27-713 27*713 27-830
27*800
27*802
27*650
Difference betwixt Poona and Bombay—
1*963 1*949 1*920
1*965
1*988
2*130
The coincidences here betwixt the barometer and mountain sympiesometers, and Mr
Treacher’s aneroids, are as close as may be.
These experiments were performed at Colonel Grant’s, at the extreme end of the
Artillery lines—his house is pretty nearly on a level with the church, the top of the
spire of which is set down in the Trigonometrical Survey at 2038 f eet above the
level of the sea. Mr Treacher’s instruments were only cut to 27*5 inches
and that belonging to the Society, cut to 23, was unserviceable, so that the doub
f#
expressed by Mr Adie as to whether or not aneroids are trustworthy below to 2 g
inches for survey purposes, remains unsolved. I do not know if there be at the presidency The name given to each of the three divisions of the territory of the East India Company, and later the British Raj, on the Indian subcontinent.