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secting purposes, because it so greatly relieved the strain upon 

 the eyes, and his own view was that if anyone wanted to do 

 practical dissection for serious work the Stephenson binocular 

 was the most convenient form. He must, however, express his 

 admiration at the ingenuity of this invention and of the way in 

 which it had been carried out. 



Mr. Karop thought the great obstacle to using an ordinary 

 compound microscope for dissecting purposes was the inversion 

 of the object and the transposition of the hands, which required 

 considerable practice to overcome. The Stephenson form at 

 least did away with this. 



The President said that he gathered that Dr. Tatham did 

 not put forward this device as an invention of a new dissecting 

 microscope, but he brought it there as a makeshift, and he 

 showed how an ordinary Rousselet portable travelling binocular 

 might be pressed into service for dissecting purposes. Dr. 

 Tatham's idea as far as he understood it was to supplement 

 and not in any way to supersede existing dissecting microscopes 

 which had been designed as such. For his own part he thought 

 the Stephenson binocular on the whole the best designed form 

 they could have for the purpose, because of its large stage and 

 the comfortable position in which it could be used, but on the 

 other hand he never saw a really good image with it, for this 

 there was nothing like the Wenham up to fin. or |in. There 

 were probably too many reflecting surfaces in the Stephenson 

 form to give the same quality of image as they got in the 

 Wenham. The main fault of the one before tbem seemed to be 

 the non-removability of the upper stage, but he did not see why 

 it should not be made removable. 



Mr. Michael thought the greater objection was the reversal 

 of the image. Some people did not appear to notice this, but 

 to him the erect image was of the utmost importance. 



Dr. Tatham said his object in bringing this design before 

 the members was to show them something which he thought 

 was likely to be of practical value. He did not pretend it to 

 be in any way a substitute for Stephenson's, which was amongst 

 other things very expensive. Personally he preferred the 

 Wenham because he had always found that the increased 

 number of surfaces had the effect of blurring the image, and 

 for this reason he had never been able to enjoy using the 



