QUEKETT MICROSCOPICAL CLUB. 251 



had been known to him for a long time, but lie had never 

 regarded them as structure, but rather as salt which had 

 crystallised out after mounting. All these fibrils consisted of 

 rows of dots connected by bars, and there always seemed to him 

 to be some difference between these and the general structure. 



Mr. E. Pitt exhibited and described the Cambridge, Minot and 

 Spencer microtomes, and, after the adjournment of the meeting, 

 gave a demonstration of ribbon section-cutting. 



A vote of thanks was accorded Mr. Pitt for his exhibition. 



At the meeting of the Club held on June 24th, 1913, the 

 President, Prof. A. Dendy, D.Sc, F.R.S., in the chair, the 

 minutes of the meeting held on May 27th were read and con- 

 firmed. 



Messrs. Frank Deed, C. Tierney, D. L. Newmarch, E. L. 

 Fen wick, and H. H. Dean were balloted for and duly elected 

 members of the Club. 



The list of donations to the Club was read, and the thanks 

 of the members voted to the donors. 



The Hon. Secretary read a note from Mr. E. M. Nelson 

 describing Koristka's new loup. The writer said that in 1885 

 he brought to the notice of the Club the then new Zeiss-Steinheil 

 loups, which had just arrived from Jena. These lenses have been 

 very popular, and have since been copied by every maker, both 

 here and on the Continent. 



There is now a new form of loup with which the Club should be 

 acquainted; it is the achromatic doublet of Koristka. The following 

 are the measured particulars (not taken from a catalogue) : 



Doublet, power 10, field 1| cm., working distance 2 cm. 



Top lens alone, ,, 5|, ,, 2 ,, 4 



Bottom lens alone, ,, 3|, 4 ,, ,, 5 



The defining pow r er of this loup is excellent, and prolonged 

 work with it seems easier than with a Steinheil ; somehow or 

 other work with a Steinheil is tiring to the eye. The price of 

 this fine lens, in a wooden box, is only 12s., but although the 

 price is so low, the quality of workmanship is particularly high. 

 Among cheap loups we so often find that the lenses are im- 

 perfectly polished, the threads of the screws badly cut, so that 

 they do not engage readily, and the quality of materials used 



