404 



Report of the Kew Committee, 



at the Observatory, and the clocks and chronometers have also been 

 compared daily. The Observatory Chronometers Arnold 86 and 

 Parkinson and Frodsbam 2408, have been cleaned and re-adjusted, 

 and the mean-time clocks, Shelton K. 0., and Shelton 35, examined 

 and re-adjusted by Dent. 



The following clocks, French, Dent 2011, Shelton K. 0., and the 

 chronometers, Molyneux No. 2125 and Breguet No. 3140, are kept 

 carefully rated as time-keepers at the Observatory. 



The mean-time clock, Shelton 35, after cleaning, &c, was bolted to 

 the wall of the chronometer-room for use in daily comparisons with 

 the chronometers on trial. 



In order to facilitate the inter-comparison of the clocks, the 

 chronometer " Parkinson " has been specially fitted up as a " hack " 

 instrument. 



At the request of the Council of the Royal Meteorological Society, 

 certain experiments were made with the view of investigating 

 Professor W. K. Zenger's solar phenomena and an examination was 

 also made of the Kew solar photographs. The results obtained were 

 however of a negative character only. A note of them has been 

 published in the ' Quarterly Journal Roy. Met. Soc.,' vol. 12, p. 215. 



A comparative trial extending over five months was made of 

 Professor McLeod's sunshine recorder (see 1 Phys. Soc. Proc.,' vol. 6, 

 p. 216), and the Stokes' instrument, which proved the results given 

 by the two instruments to be practically identical. 



IV. Experimental Work. 



Photo-nepho graph. — The report on last year's work in cloud pho- 

 tography was duly submitted to the Meteorological Council, and 

 placed by them in the hands of Professor Stokes for consideration. 



Professor Stokes having investigated the methods employed at the 

 Observatory, devised a new graphic process for determining the cloud 

 heights and motions in a much simpler manner than by the use of 

 mathematical formulas only. He invented a special apparatus called a 

 projector, which has been constructed by C. Baker, and is now being 

 utilized in the reduction of the pictures taken during the past season. 

 These have amounted to 112 cloud negatives, and were obtained in 15 

 days. 



For convenience of dealing with the cloud pictures in the projec- 

 tion apparatus with greater facility, the negatives have all been printed 

 off on paper prepared by the cyanotype process. 



Certain minor additions were made to the cameras, and accessory 

 apparatus, which have tended to facilitate their working, and their 

 action has baen fairly satisfactory ever since. There is, however, 

 still an occasional failure due to uncertainty of the duration of the 



