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various periods, and which had been kindly lent for the occasion by Messrs. 

 Crisp, Swiffc, Crouch and Curties. - Amongst these were the well-known 

 " Quekett "' dissecting stand, the Lawson Binocular was also interesting as 

 an attempt to introduce the binocular principle ; a very old one, lent by Mr. 

 Curties, had the lens connected with the base by a number of short tubes 

 with ball and socket joints; a large one made of wood, with a glass stage, 

 was well known to their President (who said somebody had called it a 

 " beetle trap"), it was very simple, and owed its origin to the Leoni form ; 

 two other forms were those devised by the late Andrew Ross ; and one by 

 Mr Swift was a sort of brass transcript of the original Quekett instrument, 

 the stand of which was made of wood. 



Mr. Crouch said the instruments on the table well illustrated .the diffi- 

 culties which microscope makers had to contend with in the matter of dis- 

 secting microscopes, for no two persons seemed to agree as to what they 

 really wanted. As a rule, an optician was required to make a certain in- 

 strument to fulfil certain purposes, and was requested to make it for not 

 more than £2 or £3, and for every dozen persons he would have to make 

 two dozen alterations in the pattern. As far as the objectives went, there 

 was not the slightest difficulty in making what had been mentioned ; but 

 until they could get observers to agree as to what they wanted, it would not 

 be worth any optician's while to take up the subject. 



Mr. Ingpen said that the question of cost depended very much upon where 

 they went to get the thing made. The Eoss dissecting microscopes cost, he 

 believed, A\ guineas, and with the doublets and accessories, it soon ran up 

 to £10. 



The President said he had one of that pattern about 30 years old, and 

 believed that it cost the sum named. 



Dr. Matthews enquired if the President had ever employed a binocular 

 eyepiece for dissecting purposes ? 



The President said he must confess that he was rather heretical as to 

 binoculars in such cases. What was really wanted was to have the object 

 well lighted and well defined. For all ordinary purposes there was nothing 

 better than a good watchmaker's eyeglass, because it was so readily adjusted 

 to the work, and, with a good orbicularis, to keep it in its place, there was no 

 trouble in using it. 



Dr. Matthews explained that he meant the ordinary binocular eyepiece, 

 and not the binocular microscope. Some persons had a difficulty in holding 

 an eyeglass properly, and to meet such cases there was another plan for 

 nsing a single lens, namely mounting it upon an elastic wire, which could be 

 moved to or from the object as required, by the pressure of the head. 



The President said that there was sometimes a little difficulty about hold- 

 ing the glass in the eye at first. When a person was beginning to do so, he 

 was apt to indulge in a good deal of impatient ejaculation ; because, when 

 he got absorbed in his work, he forgot the eyeglass, and let it drop occa- 

 sionally into the middle of his dissection. 



Mr. Ingpen thought that a large spot lens would be found of value, so as 

 to get a black ground for the illumination of delicate transparent tissues in 



