686 MR ROBERT COCKBURN MOBSMAN ON 



naturally standing higher at the southern station. The Edinburgh registers have been 

 examined for various sets of years, with the result that this great November wave 

 invariably manifests itself about the 26th of the month. The barometric fall, as might 

 be expected, is greater in the north than in the south of our islands, and probably 

 embraces the whole of Western Europe. The depression is apparently not associated 

 with steepening gradients, as there is no marked increase in the frequency of gales 

 during the passage of the low-pressure area. 



Temperature. 



The average maximum, minimum, and mean temperature, as well as the daily range 

 and daily variability of temperature, have been determined from the observations made 

 during the fifty years 1840-51 and 1857-94, the latter set of observations being those 

 taken at the various Edinburgh stations of the Scottish Meteorological Society. From 

 1840 to 1851 the observations were made at Canaan House, Grange, by the late 

 Alex. Adie, Esq., F.R.S.E. I am indebted to Mr William J. Menzies, W.S., for 

 the loan of this important register. All the values were corrected to a height of 250 

 feet above mean sea-level. 



The mean temperature of each day of the year has also been calculated on the 

 average of 100 years. 



The observations from 1770 to 1779 were taken by Mr Hoy, the station being 

 Hawkhill House till 1776 and afterwards at St Andrew Square and Pleasance. The 

 readings utilised were those made at 8 a.m. From 1795-1804 the observations were 

 made at Merchant Court* by Mr Adie, the hours of observation being 8 a.m. and 8 p.m. 

 From 1811-20 the 8 a.m. and 8 p.m. values printed in extenso in the Edinburgh 

 Advertiser were employed. From 1821-30, and from 1831-40, the daily means are 

 those deduced from the mean of maximum and minimum thermometers, the observations 

 being also made by Mr Adie. The mean daily temperatures for each of the decenniums 

 1795-1804, 1821-30, and 1831-40 were taken from Forbes' " Climate of Edinburgh ";t 

 the means for the ten years ending 1804 being first brought to the mean of the 

 maximum and minimum by the following corrections, which were obtained by com- 

 paring Adie's 8 a.m. and 8 p.m. values with a table of adopted mean temperatures for 

 the years in question. 



Jan. 



Feb. 



Mar. 



Apr. 



May. 



June. 



July. 



Aug. 



Sept. 



Oct. 



Nov. 



Dec. 



+ 0°-8 



+ l°-0 



+ l°-3 



+ l°-3 



+ 0°-8 



+ 0°-7 



+ 0°-8 



+ r-o 



+ l°-0 



+ 0°-6 



+ 0°-4 



+ 0°-4 



It may be remarked that the means for the decennium 1795-1804 include the 

 returns for the first six months of 1805. This, however, does not affect the results, 

 ten-year means having been entered in the table from which the 100-year average was 

 obtained. The period embraced in the discussion is thus really 100^ years. 



* This locality is now extinct, but it was in the vicinity of George IV. Bridge. 

 t Trans. Hoy. Soc. Edin., vol. xxii. pp. 348-49. 



