INTRODUCTION. 
DESCRIPTIONS OF INSTRUMENTS, ADJUSTMENTS, AND DATA 
FOR REDUCTIONS. 
§ 1. Postrion AND DESCRIPTION OF THE OBSERVATORY. 
1. The Magnetical and Meteorological Observatory at Makerstoun, in Rox- 
burghshire, was erected by General Sir Tuomas MaxpouGaLu BrisBane, Bart., in 
the year 1841. The geographical co-ordinates are as follow :— 
Latitude, ; ; : é 55° 34’ 45” N.* 
Longitude, . : : n 0» 10™ 3:58 W. of Greenwich.t 
Height of the barometer cistern above mean water at Berwick, 213 feet. 
The last ordinate was obtained by connecting the Astronomical Observatory 
with levels made from Berwick to the opposite bank of the Tweed, for a railway 
from Berwick to Melrose. This determination has been verified by the results of 
many series of barometrical observations, made simultaneously at Berwick and 
Holy Island by Sir T. M. Brispanz, and at Makerstoun by Miss M. BrisBane. 
The following are examples of the results taken at random :— 
Height of the cistern of the barometer in Sir T. M. BrisBANE’s library above 
mean water at 
Feet. 
Berwick, Aug. 21, 22 1837, 10 Comparisons, 4 ap preol:6 
Holy Island, Oct. 9, —4 p.m. 1839, 1... p . 226-2 
OctiylO; L6—=S0 AM Bees O Mae eaceaecne : » 2297 
NOON pacer ORS EL a nnateete cai 6 » 227-1 
a8) PE ade GE Baoobdendcaneae ‘ . 2293 
A Mipebanadooabene : - 2209 
Feet. 
Giving the results weights depending on the number of comparisons, the mean is 225-6 
The correction to the Observatory barometer cistern (by levels) é : . — 120 
Height of Observatory cistern, . F - - ° 5 d : ¢ . 2136 
* Ast. Nach., vol. x. p. 214. + Mem. Ast. Soc., vol. xi. p. 171. 
MAG. AND MET. OBS. 1843. c 
