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October number, would put the members of the Club in possession of the 

 technical nature of the glass which was employed. It was not the first time 

 they had been indebted to Professor Abbe for what they would otherwise 

 have been most unlikely to obtain. Tn 187-i Abbe published the first of his 

 remarkable scries of treatises upon the definition of the microscope, and 

 what great results had come from this they all knew. That work had 

 now been supplemented by the present great addition to the optical means 

 at their disposal. Iu the April number of the Royal Microscopical Society's 

 Journal there was a short account of the manner in which these glasses 

 were gradnated, and it was very curious to find that after Professor Abbe" 

 and Dr. Schott had made their elaborate series of experiments they were 

 disposed to leave them at that stage. Happily, however, they were induced 

 to go on, and in connection with Dr. Zeiss, subsidised by the Prussian 

 Government, the matter was carried on to its present results. He thought 

 that at present the new glass was more likely to be used for astronomical 

 purposes, seeing the very great complexity of the combinations for micro- 

 scope objectives. One of the series contained as many as ten lenses, arranged 

 in five systems, one of which was made of ordinary glass. The question 

 of getting rid of the secondary spectrum had taken a great deal of attention 

 at various times. Professor Stokes and others had worked at it, but he did 

 not suppose that any such systematic and exhaustive experiments had ever 

 before been applied to any optical theory. As regarded the new lenses, the 

 improved definition, the increase of power and convenience in use were 

 something perfectly astonishing, whilst the manner in which the objectives 

 were supplemented by proper eye-pieces showed how extremely carefully 

 the whole theory had been worked out into practice. It was Professor 

 Abbe s peculiarity that he always perfected his formulae in every detail 

 before bringing it into practice, and in the case of these new lenses the 

 whole scheme of every one had been entirely worked out beforehand. It 

 was quite a new point of departure in practical optics, and it was impos- 

 sible to say where it might lead to in the future. 



A vote of thanks to Mr. Cur ties was unanimously carried. 



Mr. Freeman said he had brought a series of sections of Spiders, cut by 

 Mr. H. M. J. Underhill, of Oxford, who, a few years ago, wrote some articles 

 on Spiders, and Diptera in " Science Gossip." Mr. Underhill had recently 

 been cutting sections of the Garden spider, Epeira Diadema, and from a 

 careful study of these sections had prepared a drawing, giving, what he 

 believed to be, a correct representation of the internal organs in their natural 

 position. Some of the results of his investigations had been given to the 

 world in an article which appeared in " The Welcome " for the present month, 

 a copy of which periodical was on the table. The principal drawing illus- 

 trating that article had been built up, as it were, from various sections taken 

 in different directions through the Spider, it being evident that a single 

 section would not convey a very comprehensive view of the interior economy 

 of the creature. He (Mr. Freeman) had also brought the original drawings, 

 which bad been kindly lent by the editor of " The Welcome." The article 



