264 BEPOET— 1891. 



by exposing to direct sunliglit and tbe ordinary atmospheric inflaences, 

 patterns of silks, wool, and cotton, specially dyed with the various 

 natural and artificial colouring matters. 



The work of purifying these colouring mattei-s, dyeing the patterns, 

 recording the dyed and faded colours of each pattern, &c., &c., must 

 necessarily require much time. Moreover, owing to the very large 

 number of colours to be examined, the long exposure needed to give 

 useful results (one year at least), and the limited capacity of the exposing- 

 frame employed, the work will naturally proceed but slowly, and will 

 extend over a period of some years. 



During the past year the Secretary of the Committee has been 

 engaged in collecting samples of the colouring matters required for the 

 investigation, and in making preliminary exposure experiments with the 

 view of determining the best method of procedure to be adopted. 



Having decided to expose the patterns in groups according to colour, 

 the work of pui-ifying and dyeing with the red colouring matters has 

 been begun, and is now in progress in accordance with a scheme in the 

 hands of members of the Committee. 



Of the 20^. originally granted to the Committee at the last meeting 

 of the Association in Leeds, the sum of \7l. 10s. has been expended in 

 the purchase of the necessary silk, wool, and cotton material, also an 

 exposing frame, which has been erected at Adel in the neighbourhood of 

 Leeds. 



Particulars of this expenditure have been forwarded by the Chairman 

 of the Committee to the General Treasurer. 



Report (provisional) of a Committee, consisting of Professors 

 M'Leod and W. Eamsay, and Mr. W. A. Shenstone (Secretary), 

 appointed to investigate the Influence of the Silent Discharge 

 of Electricity on Oxygen and other Gases. 



The Committee regrets to state that, owing to various circumstances, 

 very little further progress has been made during the past year. The 

 necessary means for securing assistance in part of the work have, how- 

 ever, lately been secured, and its continued progress may therefore now 

 be looked for ; and it is recommended that the Committee be reappointed. 

 No grant is asked for, as the necessary apparatus is at the command 

 of the Committee. 



Third Report of the Committee, consisting of Professors H. 

 M^LEODi Chairman), Eoberts-Austen (Secretary), and Eeinold, 

 and Mr. H. Gr. Madan, appointed for the Continuation of the 

 Bibliography of Spectroscopjy. 



The collection and verification of the titles of papers on spectroscopy 

 have been continued during the past year, but there is not yet suflGcicnt 

 matter for publication. 



The Committee desire to be reappointed. 



