394 



pocket lens he had ever used. It had a large field, and, being aplanatic, 

 was a thing so useful to every inicroscopist that it deserved to be brought 

 more into notice. It was made in two sizes, one of which gave a magnify- 

 ing power of six diameters and the other ten. As a condenser for low powers 

 it was admirable, and was easily used if put into a piece of brass made to fit 

 below the stage. 



Mr. Karop said that the mention of Dr. Zeiss's name reminded him that 

 his death had occurred since their last meeting — not, it could be said, before 

 his time, for he had reached a good old age. He was one of the best-known 

 makers of microscopes in the world. 



The President said with regard to the lenses mentioned by Mr. Nelson he 

 had found them of very great use for a variety of purposes ; indeed, there 

 were no lenses which he knew of that were so comfortable to work with. 



Mr. Karop said that as to using a lens of this sort as a condenser no doubt 

 it could be adapted to the purpose, but unfortunately the cheap microscopes 

 of the present day were not centred with sufficient accuracy to make a con- 

 denser of much use. The adapter was screwed by rule of thumb under the 

 stage, and was generally dreadfully out of true centre. He thought that 

 when a sum, say, of £5, was given for a student's stand without objectives 

 it should always be furnished with some kind of centring adapter below 

 the stage to carry a condenser, as this most necessary appliance for good 

 work was practically useless unless properly centred, and he had rarely, if 

 ever, found the ordinary sub-stage tube anywhere near central with the 

 optic axis. 



The Secretary reminded the members that as their next meeting was the 

 one which preceded the annual meeting it would be necessary then to nomi- 

 nate persons to serve as officers and members of Committee for the ensuing 

 year, in view of the election which would take place in February. 



Announcements of meetings, etc., for the ensuing month were then made, 

 it being intimated that at the next ordinary meeting a paper would be read 

 by the President on " Diffraction Phenomena." 



The proceedings terminated with the usual Conversazione, and the follow- 

 ing objects were exhibited : — 



Circulation of blood in egg and spawn of Trout Mr. F. W. Andrew. 



Section of the eye of a Moth Mr. H. E. Freeman. 



Larvae of Ortonia Mr. R. T. Lewis. 



,, Icerya (living) ... ... „ 



Gemmnles of Sponge, Geodia Mr. G. E. Mainland. 



Pulex penetrans 9, in skin ... ... ... Mr. F. W. Ward. 



Corneal corpuscles of Pig, stained ... ... „ 



Attendance— Members, 33; Visitor, 1. 



January 11th, 1889. — Conversational Meeting. 



The following objects were exhibited : — 



Ovum of Trachelitis Mr. F. W. Andrew. 



Smynthurus aquaticus ... ... ... ... Mr. E, T. Browne, 



