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view under strong illumination, and he had been led to the conclusion that a 

 tint between the green and the yellow was greatly superior to any other. 

 A number of specimens of glass of the tint described were sent by Mr. 

 Bridgman for distribution amongst the members. 



Mr. Ingpen said he had tried to put into practice what Mr. Bridgman had 

 described, but had not been quite successful, doubtless owing to his not 

 having cut out the diaphragm exactly as was shown in the diagram. The 

 glass he had tried, and found it to be certainly a most charming tint, and 

 far superior to the blues which were generally used for the purpose. Placed 

 under the spectroscope, it gave faint absorption bands in the blue and green, 

 and a darker band in the red just where it joined the yellow ; it was a most 

 comfortable ground for the eye to rest upon, giving a cool grey field of view ; 

 it was the result of the careful investigations of a gentleman who had given 

 many years of study to such critical subjects, and he felt sure it was worthy 

 of general adoption. 



The thanks of the meeting were unanimously voted to Mr. Bridgman for 

 his communication. 



Mr. W. H. Gilburt read a paper " On the Staining of Vegetable Tissues," 

 specimens of the process being exhibited in the room. 



Mr. Ingpen said he was glad to find that this subject had been fairly 

 launched in the Club, for he had been trying to bring it under the notice of 

 the members for some time. They must all have admired the preparations 

 by Dr. Hunt and Mr. Walmsley, which had been exhibited, and Mi - . Gilburt 

 had shown some of the most interesting specimens which they had yet seen 

 as they were prepared for the scientific investigation of the tissues, and not 

 merely as pretty show objects. The addition to the knowledge of vegetable 

 histology to be gained from specimens prepared in those ways was very 

 great, the only drawback being the apparent complexity of the process. 

 He preferred glycerine jelly for mounting specimens for general study, 

 though it was difficult to get rid of air-bubbles, and he also found aqueous 

 solutions of the dyes preferable in some cases. There could be no doubt 

 as to the great practical value of bleaching and staining as an aid to histo- 

 logical research. 



Dr. Matthews wished to emphasise the use of weak solutions. He had 

 been for some time experimenting upon the process, and found that he had 

 been using the dyes too strong, and consequently he found a halo of dye 

 surrounding the object after being mounted. He had tried to obviate this 

 by soaking the specimens in various menstrua, and had tried turpentine, 

 benzole, and others, but whenever he mounted them from a strong dye they 

 showed this defect. When, however, a weak solution was used, the mounts 

 were quite perfect, and he felt he could not too strongly urge the necessity 

 for using weak solutions. 



Mr. James Smith said he was going to suggest whether some preparation 

 of glycerine jelly or glycerine might not be used with advantage as a 

 medium for mounting, but Mr. Ingpen had already mentioned them. One 

 important advantage was that all preparations of glycerine and gelatine were 

 perfectly miscible with water; another point was that glycerine jelly had a 



