10G6 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Allman, G. J.— Obituary of G. Busk, Hon. F.R.M.S. 



Nature, XXXIV. (1886) pp. 387-9. 



American Society of Microscopists.— Ninth Annual Meeting. 



Amer. Mon. Micr. Journ., VII. (188(3) pp. 161-3. 

 The Microscope, VI. (1886) pp. 200-1, 202, 202-6 (Abstract of 



President's Address), 212. 



Bausch and Lomb Optical Co.'s New Student Microscope. [Supra, p. 1037.] 



The Microscope, VI. (1886) p. 199 (1 fig.). 



Beck, J. D.— [Working Distance of High-power Objectives.] 



[" I am no expert in optics, but I do firmly believe that the form, the con- 

 struction, the arrangement and combination of lenses for objectives can 

 be modified so as to give a working distance between the objective lens 

 and cover-glass of 1/4 in. for a 1/6 in. objective, and 1/32 in. for 1/50 in. 

 objective. I may be looked on with apparently good reason as a crank 

 for entering the field so boldly with such an idea. Things have been 

 accomplished (successfully) apparently as difficult as this enthusiastic 

 idea of mine. For example, high angles of aperture of objectives. It 

 appears that 90° was at one time considered the highest limit of angle of 

 aperture for objectives, and the man who predicted it possible to construct 

 an objective with an angle of 180° aperture certainly would have been 

 called a crank, but it has been successfully accomplished ' just the same.' 

 How much higher the angle can be applied to objectives I do not know. It may 

 be the limit. Is it not possible or even probable that the working distance 

 may be increased to the limit moutioned ? " ! (Italics ours.)] 



The Microscope, VI. (1886) p. 215. 



Beheens, W. J. — See Unna, P. G. 



Bostwick, A. E. — On a Means of Determining the Limits of Distinct Vision. 



[Post.] Science, VIII. (1886) p. 232 (1 fig.). 



Czapski, S. — Mitteilungen fiber das glastechnische Laboratorium in Jena und 



die von ihm hergestellten neuen optischen Glaser. (On the Jena Glass 



Laboratory and the new kinds of optical glass made there.) 



[Cf. this Journal, ante, pp. 316 and 849.] 



Zeitschr.f. Instrumentenk., VI. (1886) pp. 293-9 (in part). 

 Delare, Y. — Compresseur nouveau, a pressure reguliere et a retournement. 

 (New Compressor with regular pressure and reversible.) 



[Ante, p. 862.] Arch. Zool. Expe'r. et Gen., IV. (1886)xix.-xxi. (2 figs.). 



Exnek, S. — Nacbtrag zu der Abbandlung " Ueber Cylinder, welche optiscbe 

 Bilder entwerfen. (Supplement to the article " On Cylinders which form 

 optical images.") [Supra, p. 1062.] 



Arch.f. d. gesammt. Thysiol., XXXIX. (18S6) pp. 244-5. 

 Francotte, P. — Descriptions des Objectifs construits avec les verres 

 nouveaux. (Description of the Objectives constructed of the new kinds of 

 glass.) 



[Cf. ante, pp. 316 and 849.] Bull. Soc. Beige Micr., XII. (1886) pp. 100-8. 



Joum. de Microgr., X. (1886) pp. 467-70. 



Gange, C. — Lehrbuch der Angewandten Optik in der Chemie, Spectralanalyse, 



Mikroskopie, Polarisation. Praktische Anleitung zu wissenschaftlichen und 



teclmischen Untersuchungen mit Hiilfe optischer Instrumente nebst theore- 



tischer Erkl'arung der beobachteten Erscheinungen. (Compendium of Optics 



as applied in Chemistry, Spectral Analysis, Microscopy, Polarisation. 



Practical instruction in scientific and technical investigations with the aid of 



Optical Instruments and theoretical explanations of the phenomena observed.) 



[' The Microscope,' pp. 58-60 (2 figs.), 67-84 (7 figs.), 106-8,^ 173-82, 



197-8, &c] 



xi. and 463 pp., 24 pis., and 162 figs., 8vo., Braunschweig, 1886. 

 Glass, the new Optical. 



[Cf. ante, pp. 316 and 849.] Nature, XXXIV. (1886) pp. 622-3. 



See also Engl. Mech., XLIV. (1886) p. 286. 



