456 SUMMARY OF CURRENT RESEARCHES RELATING TO 



once placed near sucli position. Now, on looking through the tube at 

 the object in position and focussed, suppose I do not get as good views 

 as I had reason to exjiect, then I let the collar stand as it was, and 

 change the illumination until things are approximately as desired ; 

 this done, a slight turn of the collar adjustment will insure the maxi- 

 mum working of the objective. Now just contrast this with the usual 

 modus. Eight operators out of ten would have at once twisted round 

 the collar, haphazard-like, by 'rule of thumb,' probably wasting 

 plenty of time, and, more unfortunately still, condemning a really 

 good objective, and one that would have, with the proper manipula- 

 tions, given charming displays." 



Labelling Slides.* — Mr. S. Lockwood describes a device which 

 he has found of much service in labelling slides. It often happens 

 that the label does not afford room enough to contain the facts which 

 should accompany the si^ccimen. In such cases he writes all he can 

 on the hack of the label with a medium hard pencil, and then, with a 

 mucilage made of gum arabic one part and gum tragacanth four parts, 

 attaches the label to the slide in the usual way. As soon as dry, the 

 labelling is finished by writing the rest in ink on the upper, or face 

 side, of the label. The pencil writing on the back can be easily read 

 through the slide simply on turning it over. In this way both sides 

 of the label are utilized. 



Economical Cabinet for Slides.! — Dr. B. A. Eandall, referring to 

 the want he has found for some form of cabinet which would hold 

 securely several hundred slides and yet would not be expensive, 

 describes, as the result of some experimentation, the following 

 arrangement : — 



It consists of trays of binder's board of two sizes, the large 

 11 by 8 in., the smaller 11 by 4 in. Each of the smaller 

 consists of a solid bottom of binder's board upon which is glued a 

 second piece of the same size, from the centre of which a piece 

 10 by 3 in. has been cut. This then forms a tray about a line in 

 dejith, capable of holding ten slides. A third piece, from the centre 

 of which a portion 10 by 1 in. has been removed, is hinged to the 

 others so as to form a cover, the slot in its centre securing even deep 

 cell preparations from pressure. The larger trays differ only in 

 being of double size and holding twenty slides. Some of the trays 

 have a fourth piece of lighter material, covering the slots in the top 

 and thus rendering them complete dust-tight boxes. In series, 

 however, this is unnecessary, as the covering of each tray is completed 

 by the bottom of the one above. Each tray is, therefore, independent, 

 a rubber strap about it rendering it entirely secure for holding or 

 transporting specimens, while any number of them can be combined 

 and further secured in a wooden case, making a neat and safe cabinet. 



Such a cabinet, 12 in. by 9 in. by 10 in. in height, will contain a 

 series of closed trays capable of holding 500 slides. Each tray must 

 be withdrawn from beneath those above it in order to get at its 



* Amer. Mon. Micr. Jourii., iv. (1883) p. 64. 



t 'The Microscope,' ii. (1882) pp. 134-5, from 'Western Medical Reporter.' 



