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quite clean, it might be useful to members to knowthat a solution of bichromate 

 of potash in water, with the addition of some sulphuric acid, was a very excellent 

 cleaning fluid. The proportions to be used were — bichromate of potash, 1 oz., 

 sulphuric acid, 1 oz., water, 1 pint ; it would be found to take off all kinds of 

 dirty stains, and was especially useful where the slides had previously been 

 used for balsam. 



The Secretary inquired whether it would take off old balsam from slides ? 



Mr. Suffolk replied that the balsam should be taken off first by putting the 

 slides into soda, and then the slides could be cleaned off afterwards with the 

 fluid. 



Dr. Matthews recommended a strong infusion of nut galls as a very excellent 

 thing for cleaning glass slides j it cleaned them chemically and not merely 

 mechanically. 



The Secretary said it was a very great nuisance, cleaning off old balsam from 

 slides, and he was very glad to learn how it might be done without much 

 trouble. 



Mr. B. D. Jackson had found a mixture of distilled water, alkali, and tripoli 

 very useful for cleaning glass, especially where a little friction was of no conse- 

 quence j he would be glad to communicate the formula for making this mixture 

 to any member who desired to try it. 



Mr. Henry Lee expressed his thanks for the information which had been given ; 

 he had never in mounting thought either time or trouble to be an object, as he 

 always desired to do the thing well, but then the thing was how to do it. He 

 thought it would not be out of place to say that he should like to see the meet- 

 ings of the Club return more to their old conversational style than had latterly 

 been the case ; he thought all would agree with him that the evening had not 

 been less plessant because they had no paper read, and he believed it would be 

 better for the Club on the whole if they aimed less at scientific than con- 

 versational evenings. 



Dr. Matthews said that it would no doubt be remembered that at the last 

 gossip meeting he showed some turkey parasites which were mounted in such a 

 way as to be unusually transparent, and yet showed all the internal structure 

 in a very perfect manner. He had since then been asked how this was done, 

 and he wished to say that he first placed them in weak spirit and water, then 

 transferred them to stronger spirit and water, and afterwards to strong tur- 

 pentine, and after remaining there a sufficient time he mounted them in balsam. 

 They were not treated with liquor potassse or any other destructive fluid, and 

 hence the entire system of trach were preserved intact and were shown in a 

 remarkably clear and beautiful manner. 



Mr. Henry Lee asked if they were not rendered stiff and difficult to lay out 

 after being prepared in this way. 



Dr. Matthews said they were not at all so, and the method he had described 

 showed the sti-ucture so admirably that he most strongly recommended it. 



The President said that he quite agreed with Mr. Suffolk as to the necessity 

 for extreme care and cleanliness in mounting objects in glycerine. He thought, 

 however, that the manner in which the varnish was applied to cement the thin 

 glass cover, had more to do with the preservation of the joint than the nature of 

 the varnish used. ■ Fifteen ytars ago he had employed for the purpose common 

 Brunswick black, improved by adding a little solution of indiarubber in coal 

 naptha. When this was dry the edges were very carefully wiped before putting on 

 another layer. Several layers were subsequently applied, an interval of a day 



