154 SUMMABY OF CURRENT RESEARCHES RELATING TO 



portion of the drum. Each of the smaller zones is marked with the 

 figures 1, 2, 3, and 15. When the drum is in order for work, it rotates 

 with the screw, which is marked g g in fig. 53, vol. iii. (1883) p. 302. 



The left half of the drum A B is held in position by the screw S, 

 and may be rotated independently of the right half A' B', or |of the 

 screw g g, by the aid of a handle which fits the holes x x x. 



When the half A B is adjusted to the half A' B', in the manner 

 represented in the figure, the fifteen equal parts into which the zone 

 B is divided exactly correspond to the same number of parts in the zone 

 B', so that the grooves which mark these parts in one zone, become 

 continuous with those of the other zone. Thus adjusted, the spring, 

 which rides on the zones B B', with a sharp edge parallel to the grooves, 

 will give fifteen sharp clicks in the course of one rotation of the 

 drum, the click being heard every time the sharp edge falls into 

 coincident grooves. In order to adjust for fifteen clicks, it is only 

 necessary to rotate A B until groove 15 becomes continuous with 

 groove 15 of the opposite half (A' B'). For one click in one rotation, 

 the grooves 1, 1 must be made to coincide ; for two clicks the grooves 

 2, 2, and for three clicks the grooves 3, 3. The intervals between 

 successive clicks may thus be made to correspond to 1/1, 1/2, 1/3 or 

 1/15 of a complete rotation of the drum, and the thickness of sections 

 corresponding to these intervals should be respectively "015, •0015, 

 •005, -001 mm. 



AcHESON, G. — Biological Study of the Tap Water in the School of Practical 

 Science, Toronto. 



[Methods of examination — Diatomacese — Desmidiacese — Phycochromaceae 

 — Schizophytse — Protozoa — Vermes — Arthropoda.] 



Froc. Ca7iad. Institute, I. (1883) pp. 413-26 (1 pi. to follow). 

 Aby, J. E. — Microscopical Technology. On the exhibition (sic) of Canada 

 Balsam. 

 [Directions for mounting sections of tissues in Canada balsam.] 



Sci.-Gossip, 1884, pp. 5-8, 

 Ady's (J. E.) New Morphological Institution [for the production of micrographical 

 preparations, and especially of rock and mineral sections]. 



Sci.-Gossip, 1883, pp. 276-7 ; 1884, p. 18. 



See also Nature, XXIX. (1884) p. 283. 



Ami, H. M. — Use of the Microscope in determining Fossils, with especial reference 



to the Monticuliporidse. Science, III. (1884) pp. 25-6. 



Aylwaed's (H. p.) Pond-life Apparatus. [Vol. III. (1883) p. 911.] 



Sci.-Gossip, 1883, p. 276. 

 Baebe, p. — Sur un precede de preparation synoptique d'objets pulverulents. 

 Diatomees des guanos, terres fossiles, &c. (On a process of synoptic prepa- 

 ration of pulverulent objects. Diatoms from guano, fossil earths, &c.) 



IPost.'] Bull. Soc. Belg. Micr., X. (1883) pp. 16-8 (1 pi.). 



Belfield, W. T. — The Microscope in the detection of Lard Adulteration. 



Proc. Amer. Soc. Micr., 6th Ann. Meeting, pp. 97-103 (1 pi.). 

 Bennett, C. H. — Mounting Entomological Slides. 



[Treat the object for a week or a month, as the case may require, with liq. 

 potassse until thoroughly bleached ; then, without removing the contents 

 pf the cavities, or in any way subjecting to the slightest pressure, mount 

 in glycerine in a cell of ample depth so as to allow the object to retain 

 its natural form and position.] 



The Microscope, III. (1883) p. 220. 

 Beaman, B. — Microscopic Evidence of the Antiquity of Articles of Stone. 



Amer. Mon. Micr. Jvurn., V. (1884) pp. 14-5. 



