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The Plates illustrating "Baker on the Microscope" Mr.Hawkins Johnson. 



Quaritch's " Catalogue of Books " ... ... from the Publisher. 



" Annals of Natural History " by purchase. 



"The American Journal of Microscopy" ... from the Editor. 



" The Medical Examiner." Weekly „ the Editor. 



" Proceedings of the Belgian Microscopical "i . , Societv 



Society > " J ' 



Photographs for the Album of Mr. S. A. Johnson, Mr. W. W. Reeves, Mr. 

 Alpheus Smith, and Mr. Topping were also presented. 



The thanks of the Club were unanimously voted to the donors. 



The following gentlemen were balloted for and duly elected Members of 

 the Club : — Col. H. Basevi, Mr. J. L. Luscombe, Mr. Bernard Smith, Mr. 

 Saml. Smith, Mr. G. H. Wallis, Mr. W. Walters, and Capt. Weatherley. 



The President announced the forthcoming Soiree of the Croydon Micros- 

 copical Club, and invited the assistance of such members of the Q. M. C. 

 as might be able to be present on the occasion. 



Dr. James Edmunds then addressed the meeting " On a new Immersion 

 Paraboloid Illuminator." He commenced by drawing the attention of the 

 members to two objects — Amphipleura pellucida and Podura Scale — ex- 

 hibited in the room, in order to illustrate the action of the Illuminator 

 which he was about to describe. The first was an ordinary valve of A. 

 pellucida, measuring about - 005 inch in length, and marked with transverse 

 lines counting more than ninety thousand to the inch, the valve being dis- 

 played upon a soft black background, and its lines with their interspaces 

 showing as brilliant green and black bands. These lines and their inter- 

 spaces — together measuring in round figures, nearly 200,000 to the inch- 

 were distinctly separated, and made visible to the eye. The valve was seen 

 through an immersion l-16th by Powell and Lealand and, so far as he (Dr. 

 Edmunds) had learnt, A. pellucida had never been shown thus by any illu- 

 minator that had previously been devised. The Podura was an ordinary 

 scale of Lepidocyrtus curvicollis, lying in air, solidly upon the slide, with 

 a thin cover close over its upper surface. The objective was a new-for- 

 mula immersion -|th, by Powell and Lealand. It would be observed that 

 a brilliant positive image of the podura scale — also upon a perfectly black 

 background — was seen, and that the " markings " were shown demonstra- 

 tively as minute featherlets, projecting up from the scale membrane. Podura 

 Scale appeared to resemble a mat in structure, but its membranous basis 

 was so hyaline that, under this light it blended with the slide, and trans- 

 mitted light into the featherlets without itself becoming luminous. By 

 shifting the lamp from side to side, or by altering the mirror to a small 

 extent, these featherlets were seen to become shaded on either side, and on 

 further alteration their images became so blended as to render optical defi- 

 nition impracticable. In a particular light the tips only of the featherlets 

 were illuminated, and these tips appeared as brilliant beads arranged on 

 the scale in exact accordance with those ends of the markings which were 

 towards the free end of the scale. This might easily be demonstrated by 

 plotting out the "markings" under one light, their beaded tips — as seen 



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