PROFESSOR FORBES ON THE CLIMATE OF EDINBURGH. 331 
15. The original observations were far more extensive. Stimulated probably 
by Professor PLAYratr’s example and advice, Mr Apr commenced what appears 
to have been a very careful register of the thermometer, barometer, wind, and 
rain, on the Ist January 1795. After continuing this register with great 
punctuality for more than ten years, it came abruptly to a close about the middle 
of 1805. It seems certain that Mr Apis then discontinued it, not from any want 
of interest in the subject, but because he considered that he had amassed suffi- 
cient materials for ascertaining the peculiarities of the climate of Edinburgh. 
For he reduced these ten years’ observations with care, and not only so, but pro- 
jected the whole in neat curves now in the possession of his family. These 
observations were made in Merchant Court, a locality now apparently extinct, 
but which was close to Merchant Street, near George IV. Bridge, in the old town 
of Edinburgh. Its elevation above the sea was, according to Mr James JARDINE, * 
230 feet. The distance from Windmill Street, the locality of Professor PLAYFAIR’s 
observations, was inconsiderable. The observations were made at 8 a.m. and 
8 P.M. | 
16. Nearly fifteen years elapsed from 1805 without observations being made. 
I shall afterwards state the source whence I have attempted to supply this blank. 
17. In 1821 Mr Ante resumed his observations at his villa of Canaan Cottage, 
in a sheltered valley about a mile and a quarter south from his former locality. 
Its elevation was 260 feet above the sea.+ The observations of the common 
thermometer and barometer were made at 10 a.m. and 10 p.m. instead of eight 
o’clock, as formerly. From 1822 the observations included the maximum and 
minimum temperature. 
18. These observations were continued until 1850 inclusive, by Mr Adie or 
some member of his family. But it is important to observe, that from the middle 
of May 1831 to the middle of May 1838, the locality was removed to No. 9 
Regent Terrace, on the Calton Hill, in the new town of Edinburgh, 246 feet above 
the sea, about five furlongs N.E. from his first station in Merchant Court, but in 
a far opener and more airy situation. In 1838 the old residence at Canaan 
Cottage was resumed. 
19. Thus we have consecutive observations from 1795 to 1804 both inclu- 
sive; and again consecutive observations from 1821 to 1850 both inclusive, at 
two localities distinct from the former. The changes of locality and exposure are 
no doubt unfavourable to the perfect comparability of these observations. Never- 
theless the considerable continuity of the observations in each locality enables me 
to affirm, after comparing the mean results, that the change of position (the 
* See Sir D. Brewsrer’s Memoir on the Mean Temperature of the Globe (Edin. Trans, vol. ix. 
pp. 209, 210), where also the mean temperature is deduced from Mr Jarprne’s observations on the 
springs of the Pentland Hills to be 47°1. 
+ Edinburgh Journal of Science, vol. i. In later volumes it is stated at 300 feet, but this is 
certainly too high. By the Ordnance Survey Map it would appear to be about 280 feet. 
VOL. XXII. PART II. 4Q 
