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he had turned one into a microscope table, and found it answer very well, 

 though he did little more than cut down the legs and make it stand firmly 

 at the proper height to use comfortably. The first requirement was that a 

 table should be sound and firm, those which revolved were not satisfactory 

 on account of being so very unsteady. Nothing to his mind was better than 

 the good old kitchen table form. 



Mr. Karop said the top ought to be at least an inch thick when planed down, 

 and he had found 2ft. 9in. x 1ft. Gin. amply large enough for all purposes. 



The Rev. H. J. Fase thought that Mr. White, in his large experience had 

 forgotten a very convenient form which he remembered to have seen at 

 his house some years ago. It was a kind of revolving desk which was 

 simply placed upon an ordinary dining table. 



Mr. White said that he had found the contrivance referred to by Mr. Fase 

 a very useful thing when one had a friend to whom it was desired to show 

 objects under the microscope, and it was certainly very much better than a 

 revolving table. It was made out of a piece of mahogany 16 inches square 

 to which was fixed a heavy leaden foot, and some small castors on which it 

 would turn freely when stood on an ordinary table. It was quite large 

 enough to hold the lamp as well as the instrument, and could be passed or 

 turned round to anyone else without altering their relative positions. 



Mr. Ingpen said that the old device of a revolving table was very useful 

 if only it could be made steady. With regard to the question of vibration, 

 he remembered that there was an article in their Journal some years ago by 

 Mr. Bridgeman, of Norwich, in which he proposed to get rid of vibrations 

 by using two boards separated by indiarnbber rings, and connected together 

 by strong indiarubber bands, the idea being that the cross vibrations allowed 

 by the indiarubber neutralized others. In working with high powers the 

 vibrations troubled him so much that he thought of mounting the micro, 

 scope on a column isolated from the floor, after the manner of a transit in- 

 strument. 



Dr. Matthews said there was another form of revolving table which was 

 simple and effective. It consisted merely of two boards clamped and 

 planed so as not to be liable to warp ; the size should be about 16 inches 

 square by £-inch thick, pivoted together in the centre without being actually 

 fastened to each other, so that the top one would turn freely upon the one 

 underneath. The best annuller of vibration was simply a quire of blotting- 

 paper clamped to the edge of the board ; by this means all vibration was re- 

 duced to the smallest possible degree. It was also of advantage to put 

 under the boards a piece of soft indiai'ubber, which served the purpose 

 of green baize, and acted like the blotting-paper in reducing vibrations. 

 This plan was much better than the table referred to by Mr. Ingpen, and he 

 could strongly recommend it. 



Mr. Ingpen said he should not have omitted to mention that a great deal 

 depended upon the character of the microscope as to the kind of vibrations 

 which would affect it. Some time ago a paper on the subject was written 

 by Dr. Carpenter, who narrated his experiences of working with several 



