Page:History of the Royal Astronomical Society (1923).djvu/171

 , 860-70] ROYAL ASTRONOMICAL SOCIETY 145 One of the main objects of these ascents was to extend and improve our knowledge of the relation which exists between increase of elevation and the corresponding variations of temperature and moisture, these variations in their turn having an intimate bearing on the theoretic determination of atmospheric refraction. The results of Mr. Glaisher's observations indicate that the hypothesis of a diminution of i Fahr. of temperature for every additional 300 feet of elevation must be abandoned even for incon- siderable heights above the earth's surface. . . . Through the first 1000 feet under a cloudy sky there is a change of i Fahr. for every 213 feet, but if the sky be clear there is a diminution of i Fahr. for every 139 feet. At extreme heights, such as between 25,000 and 30,000 feet, it requires a full 1000 feet of additional altitude to cause a diminution of temperature of i Fahr. Herein is found the first discovery of indications of what in modern days is recognised as the stratosphere. It is difficult to see how Lee, in speaking in 1863 of Argelander's achievement, " his Survey of the Northern Heavens," could have missed the opportunity of a fine address. It would almost seem as if he could never have had access to any of the three volumes, 3, 4, and 5, of the Bonn Observations, which constitute volumes I, II, and III of the Bonn Catalogue, though they bear the date 1859, 1861, and 1862 respectively. He appears rather to have contented himself with the slight information contained in two notes published in the Monthly Notices : the first being a report of progress of the charts communicated to Carrington by Kriiger at the request of Argelander in December 1861 (M.N., 22, 57) ; and the second being a note of twenty-six lines in the Council's Report in r862 February (M.N., 22, 125). Lee would seem even to have read Carrington's comment on Kriiger's note unmoved. It deserves to be transcribed here : The Fellows of the Society, and all to whom this account comes, cannot fail to admire the stately progress of this enormous work, which, simple in its conception, and free from insurmountable difficulties in execution, would appal many an astronomer by its vast extent. The three volumes of the catalogue contained the magnitude, R.A. and Dec. reduced to epoch 1855-0 approximately the mean date of the zone observations completed between the years 1852 and 1859 of 324,198 stars. The catalogue was completed by the issue of an atlas of forty charts containing a representation of every star in the catalogue ; thirty-seven of them had been published at the date of Lee's address, and the forty were complete by the summer of 1863. 10