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brilliant illumination may be obtained by the use of the silvered 

 side reflector. A bull's-eye is used to parallelise the light, the 

 light to be level with the reflector, and the bull's-eye to be centred 

 on the same line. 



The most powerful and best opaque illuminator is the parabolic 



side silver reflector. This is fitted to the object-glass itself. It 



is very simple to use, and throws light upon the object from 180° 



of arc. The Sorby reflector and the Lieberkuhn were also shown, 



and their advantages and disadvantages pointed out. The next 



exhibit was the thin glass reflector at the back of the object-glass. 



This is a very good illuminator of the Sorby type, and consists of 



a transparent thin glass placed at an angle of 45°. It does not 



reflect so much light as the silvered mirror, but does not obscure 



any portion of the objective. The Beck thin glass illuminator 



consists of a transparent thin glass disc used at an angle of 



45°, placed in a revolving adapter fitted into the nosepiece and 



above the objective. Light is thrown on the thin glass through 



a hole in the adapter, and is then reflected by the glass disc on 



to the object, the objective acting as a condenser and focussing 



the light upon the object, thus forming a very powerful all-round 



illuminator. This form of illuminator is difficult to use with dry 



lenses unless the object is uncovered, as a strong glare is generally 



caused, due to reflection from the cover-glass. The prism vertical 



illuminator and the new Rosenhain reflector were also shown. 



On the motion of the President, a very hearty vote of thanks 

 was accorded to Mr. Conrad Beck and to his assistant for the 

 demonstration just given. 



The lion. Secretary said that he had received a letter from one 

 of their members, Mr. J. Carrington, P.O. Box 48, East London, 

 South Africa, in which he offered to exchange material and asked 

 for correspondence on microscopy. 



A paper on " Water-bears, or Tardigrada," by Mr. James 

 Murray, was read by Mr. D. J. Scourfield. 



Mr. Scourfield made a few remarks on the " encystment " of 

 Tardigrada, which Mr. Murray had been fortunate enough to 

 observe. This encystment occurs in the following manner : At 

 some moultings the animal remains within the old skin, becomes 

 darker in colour, and the legs almost disappear, becoming small 

 knobs. About a week later another cyst is formed inside the 

 previous one, and looks very like an egg. At first all the organs 



