THE 



MONTHLY MICROSCOPICAL JOURNAL. 



FEBKUAEY 1, 1871. 



I. — Observations on the Use of the Aeroconiscope, or Air-dust 



Collecting Apparatus. By E. L. Maddox, M.D. 



(Head hc-fore the Eoyal Miceoscopical Society, Jan. 11, 1871.) 



Plates LXXIII. and LXXIV. 



The use of tlie instrument describecl and figured in the Monthly 

 Journal of the Eoyal Microscopical Society, June 1st, 1870, for 

 collecting, through the natural force of the wind, particles floating 

 in the atmosphere, and which is now designated the Aeroconiscope, 

 enables me to offer a brief sketch of some of 

 the results obtained, also to extend the plan of 

 cultivating the germs collected on the thin 

 covers. 



Wishing a more simple method of forming 

 the air-space than with the tinfoil arrangement 

 previously described, a preparation of mastic, 

 wax, chloroform, &c., was made, which, by aid 

 of a small sable-brush, would be drawn across 

 the surface of a very slightly-warmed slide, so 

 as to form a square, the size of the thin cover, 

 but with one side prolonged to the edge of the 

 slide, and the other brought nearly to meet 

 that side, and then turned down also to the 

 edge, so as to allow a small channel for the 

 entrance of air. This method answered the 

 purpose, the covers, by a very gentle pressure 

 along the edges, remaining well fixed on the 

 cement. Also, to form a simple damp culti- 

 vating chamber, to contain a number of slides 

 at once, a large new ordinary writing-slate, 

 with a well-made frame, had the latter deep- 

 ened on one surface by an extra frame about 

 one-sixth of an inch thick, and furnished with a couple of elects 

 at two ends, with a stop or check on a third side. After well 

 cleaning the slate, a leaf of thick white blotting-paper was laid on 



VOL. v. E 



