X Introduction to the Makerstoun Observations, 1843. 



Comparisons of simultaneous observations made at the Edinburgh Observatory 

 by the late Professor Henderson, and at the Makerstoun Observatory, gave the 

 difference of heights of the barometer cisterns : — 



Feet. 



Edinburgh Observatory minus Makerstoun Observatory, 130 



Height of the Edinburgh barometer cistern above mean water at Leith (by levels), 352 



Height of Makerstoun barometer cistern, . 222 



2. The Magnetic Observatory is situate nearly on the summit of a ridge, which 

 occupies the left or northern bank of the Tweed, being 540 feet distant from, and 

 80 feet above that river. The Astronomical Observatory is upon the highest part 

 of the ridge, 140 feet due west of the Magnetic Observatory. A fair horizon is seen 

 from the Observatory hill, being bounded about 10 miles to the east by a slightly 

 swelling ground, which, to the east-south-east, seems to join the Cheviot Hills. The 

 view is bounded about a mile to south and south-west by a ridge, forming the right 

 bank of the Tweed ; about 500 feet to the south-west and north-west by masses of 

 trees in the Makerstoun grounds ; and from 1 to 3 miles to north-west, north, and 

 north-east, by an elevated ridge, which forms, to some extent, the northern boundary 

 of the valley of the Tweed. From north, by the east, to the south, the elevation of 

 the horizon, with a slight exception, is under 2° ; from the north to the north-west, 

 increasing from 2° to 4° ; from the north-west to the south-west, the tops of the 

 trees are elevated from 5° to 8° ; and from the south-west to the south the eleva- 

 tion is under 4°. The highest point of the Cheviots, which is 2G56 feet above the 

 level of the sea, is about 18 miles to the east-south-east ; it is occasionally referred 

 to in the meteorological remarks on clouds. 



3. The Observatory hill, it is believed, is composed of felspathic trap. The 

 Tweed, immediately to the south, and for a mile to the east and west, flows more 

 or less through this rock, which does not appear upon any part of the hill. The 

 opening for a foundation to the Observatory shewed only masses of rolled pebbles, 

 and boulders of grey wacke and trap. 



4. The Observatory is rectangular in its plan, 40 feet by 20 feet internally. It 

 is formed of wood ; copper nails were used ; and iron carefully excluded from every 

 part of the structure. The pillars for the magnetometers and telescopes are of 

 stone, from 22 inches to 19 inches in diameter, and are placed upon excellent stone 

 foundations, completely disconnected with the floor, and every part of the building. 

 By a reference to the plan and elevation, the following details will be understood. 

 (Plate I.) 



There are two windows to the south, with the door between ; and three to the 

 north, which open like folding doors. The dimensions of the principal apartment 

 are, 40 feet long, 12 feet broad, and 12 feet high. The two ante-rooms are each 

 15 feet long, 7 feet broad, and 12 feet high. The instruments are indicated in the 

 plan as follows : — 



