644 PROCEEDINGS OF THE SOCIETY. 



had been used for both micro- and tele-photography. In order to adapt 

 the camera to the Microscope for tele-photography, two objectives, of 

 long and short focus, were used ; the long-focus lens was placed in front 

 and the short one at the back, so that a telephoto combination was 

 obtained. 



The President thanked Mr. Davidson for his account and demonstra- 

 tion. From what they had just heard it seemed that the apparatus was 

 one which might be said to bring the telescope within reach of all. 



Mr. Conrad Beck said that Mr. Davidson's apparatus consisted of a 

 telescope in which the eye-piece, instead of being of the usual nature, 

 consisted of an entire elaborate Microscope, and although, for the con- 

 venience of the possessor of a Microscope, it might occasionally be 

 interesting to use his instrument as a very high-power eye-piece of a 

 small telescope, the optical effect would not be as good as using a small 

 telescope by itself. 



Mr. Davidson replied that all he claimed for his apparatus was that 

 by using stops on the lens a very much better defioition of the image, 

 which was focused in air on the plane of the Microscope-stage, was 

 obtained than when no such stops were used. He did not regard his 

 instrument as a substitute for the telescope, but as one that enlarged the 

 sphere of usefulness of one's Microscope. 



The thanks of the Society were accorded to Mr. Davidson for his 

 demonstration. 



Mr. Heath then exhibited a " New Safety Device for High-power 

 Lenses and Cover-glasses," which he had made in consequence of an 

 accident to some of his preparations when on exhibition. The arrange- 

 ment consisted of a disk fitting over the objective, and sufficiently thin 

 not to disturb the performance of the lens, and carrying an adjustable 

 stem, the point of which engaging with the stage, prevented the tube 

 being lowered farther than a pre-arranged distance. With this device 

 he claimed it to be quite safe to use a -^^ objective. It admitted of 

 legitimate focusing by those qualified to do it, but effectually prevented 

 an inexperienced or careless visitor from doing damage. 



The thanks of the Society were accorded to Mr. Heath for his little 

 device. 



On behalf of Messrs. W. Watson and Sons, Mr. Watson Baker 

 exhibited : — 



1. A Microscope intended for workshop use, and so arranged that 

 it could be placed either upon a cylinder or on a flat surface and stand 

 firmly. The Microscope was fitted with a f-in. objective, and could be 

 used with any power up to a -^-in. The Microscope was placed over the 

 metal to be examined and the battery switched on, thereby lighting a 

 small electric lamp fitted to a new form of vertical illuminator. The 

 instrument was designed for the use of those who were accustomed to 

 Microscopic work. 



2. A special Microscope devised by Mr. E. W. Winder, Director of 

 a steel works at Sheffield, to permit the examination of the surface of a 



