ZOOLOGY AND BOTANY^ MICEOSCOPY, ETC. 725 



Hitchcock, R. — Messrs. Rogers' Microscopic Scissors. 



[Twelve pairs of perfect scissors which are overbalanced by a half-grain 

 ■weight.] 



Amer. Mon. Micr. Journ., IV. (1883) p. 139. 

 „ „ The American Association for the Advancement of Science. — 



Meeting at Minneapolis. Amer. Mon. Micr. Journ., IV. (1883) p. liO. 



„ „ Notes from Abroad. 



[Visit to E. Ward — Quekett Club Gossip Meeting — Fresh-water Medusa.] 

 Amer. Mon. Micr. Journ., IV. (1883) pp. 147-9. 

 HoBSON, B. — The Electric Light applied to the Microscope. 



[Describes his experience of the Stearn-Swan lamps, with description of his 

 simple apparatus for applying it. " I am perfectly satisfied with the 

 electric light, it is quite steady, very convenient, can be used close to the 

 object, and shows colours like daylight. I believe that it is perfectly 

 adapted for photography. The Rev. W. H. Dallinger, F.R.S., tells me 

 better light for the Microscope can be obtained in other ways, but I like 

 it more than anything I have seen."] 



Sci.-Gossip, 1883, pp. 171-2 (1 fig.). 

 „ „ On Drawing Microscopic Objects. 



[Description of a " micrographic camera " made from a tin biscuit canister. 

 — C. G. Leland's receipt for making tracing paper which can be recon- 

 verted into ordinary opaque drawing-paper. — J. C. Leake's dark tent, and 

 miscellaneous remarks.] 



Sci.-Gossip, 1883, pp. 193-6. 

 International Bureau of "Weights and Measures. 



[Describes the " Comparateurs " for lengths with two Microscopes and 

 micrometers.] (In part.) 



Nature, XXVIII. (1883) pp. 464-6 (2 figs.), from La Nature. 

 [Jaubert's] Institut populaire du Progres — Section de Micrographie— Laboratoire 

 et Ecole populaires de Micrographie. 



[Announcement of the section having been definitively constituted, and 

 statement of its objects, &c.] 



Les Sciences, I. (1883) pp. 81, 45, and 46 ; see also p. 3. 

 Jung, H. — Neuer beweglicher Objecttrager fur Mikroskope, (New movable 

 Stage for Microscopes.) \_Post.'] 



Zeitschr. f. Instrumentenk., III. (1883) pp. 246-7 (1 fig.). 

 Leitz Oil-immersion Objectives. 



[Notice of l-15th in. and l-18th in. (or l-20th in.) of 1-26 N.A.— the work- 

 ing distance of the latter '01 in. ] 



Micr. News, III. (1883) p. 265. 

 Lowe, C. A. — A Substitute for a Revolving Table. 



[" Board set on rollers and carrying the Microscope and lamp round a house 

 table by revolving on a centre through the medium of an arm on stalk. 

 ... As a screw put into a mahogany table would be objectionable," a 

 centre is made of two disks of wood between which the stalk revolves 

 freely on a screw, a 10 lb. weight on the uppermost disk preventing the 

 centre from slipping about the table.] 



Sci.-Gossip, 1883, pp. 208-9 (1 fig.). 

 MiQUEL, P. — ^Atmospheric Dust and Germs. 



[Extract from his paper communicated to the Faculty of Medicine, Paris, 

 with figures of Apparatus — Post.'] 



The Microscope, III. (1883) pp. 111-19 (11 figs.), 

 from the Scientific American, from Le G^nie Civil. 

 MooEE, A. Y. — The Measurement of Numerical Aperture. 



[Describes the method suggested by Prof. Abbe, Vol. I. (1881) p. 400, of 

 measuring the diameter of the emergent pencil with an auxiliary Micro- 

 scope.] 



The Microscope, III. (1883) pp. 97-9. 

 Ondeedonk, C. — American and German Objectives. 

 [Complaint of the high price of the former.] 



Amer. Mon. Micr. Juurn., IV. (1883) pp. 159-60. 



