( 90 ) 

 PROCEEDINGS OF SOCIETIES. 



Microscopical Society, May 23rd. 

 On a new form of Microscope. By Robert "Warington, Esq. 



In carrying on the observations in my small Aquarium, which have 

 for some time past occupied my leisure hours, I was very anxious 

 to bring the microscope to my aid in examining the minute organ- 

 isms or delicate structures of the creatures I had the opportunity 

 of noticing, and which had been maintained for a considerable 

 period in a healthy condition ; at the same time it was important to 

 do this without disturbing them from the natural position they had 

 taken up, or removing them from the water. It occurred to me 

 that I could best effect this object by attaching the microscope to the 

 edge of the table, on which the aquarium was placed, by means of 

 a clamp, and that by shifting this along before the front of the 

 tank I could range over all the objects situated at that part. 



In searching among some old chemical apparatus for a clamp 

 likely to be suited for this purpose, I happily found one that had 

 been employed for carrying the plates or subjects in an electrotyping 

 trough, and which appeared exactly adapted for the object I had 

 in view, being fitted with two ears which projected from the back, 

 and through each of which a circular hole was drilled for carrying 

 a rod, one of them being supplied with a binding screw for the 

 purpose of adjusting it to any desired length. As this clamp fitted 

 well to the edges of the table, I had only to get an ordinary micro- 

 scope body arranged, with a cradle-joint and circular rod attached 

 to the back and end of the bar which usually carries the rack and 

 pinion of the coarse adjustment, and the desired requirements were 

 fulfilled. By this means several motions of the instrument were 

 obtained : first, the power of elevation or depression, by means of 

 the rod, in the front of the tank ; second, the focussing for distance 

 by the rack and pinion ; third, angularity in the position of the 

 body by the cradle-joint ; fourth, the traversing motion along the 

 margin of the table, and also a curvilinear motion of the instrument 

 by the rotation of the circular rod in the back of the clamp. 



This object having been completed to ray satisfaction, it next 

 became a question whether the instrument, with a few additions, 

 could not be turned to more general utility as a travelling micro- 

 scope, particularly for use at the sea-side. To effect this I procured 

 a small flat block of wood having an upright piece fashioned at 

 right angles across its upper surface, on the edge of which the 

 clamp or saddle could be screwed, and the body of the instrument, 

 being adjusted at right angles to the rod, thus brought to act over 

 any vessel, as a saucer or plate, containing the object to be 

 examined ; the length of the rod being the limit of the distance 

 over which it would range. This arrangement rendered the instru- 

 ment doubly useful, and was found to realize all my anticipations. 



