594 SUMMARY OF CURRENT RESEARCHES RELATING TO 



Davis, G. E. — " To our Subscribers." — " Om- Free List." 



incr. News, III. (1883) p. 182. 

 Glazebkook, R. T.— On Polarizing Prisms. ISupra, p. 579.] 



Froc. Phijs. Soc. Lond., V. (1883), pp. 204-16 (6 figs.). 

 Govi. — Intorno alio scopritore di una siugolare illusione ottica. (On the disco- 

 verer of a singular optical illusion.) [/"os^.J 

 [With remarks by Sig. Eespighi.] 



Atti R. Accad. Line. Trans., VII. (1883) pp. 183-8. 

 Grattakola, G. — Su un possibile errore nelle misurazioni micropetrografiche. 

 (On a possible error in micropetrogiapliic uieasurenieuts.) 



[In measuring, by means of the fine adjustment screw, the vertical dimen- 

 sious of an object inclosed in a transparent medium, such as a microlith 

 in quartz or felspar, fir the vertical distances between two pointd in such 

 a medium — in short differences of level — the true difference is equal to that 

 shown by the direct reading of the screw multiplied by the refractive 

 index of the medium.] 



Atti Sue. Tosc. Sci. XaL, Froc. Verb., III. (1883) pp. 244-6 (1 fig.). 

 Gkimm, J. — See Colien, E. 

 Hailes, H. F. — Adapters for Microscopes. 



[Note on letter of J. A. OUurd infra as to Nelson's and Curties' Adapters.] 



En<jl. MecL, XXXVII. (1883) p. 385. 

 Hardy, J. D. — Gas lamp for microscopic use. 



[Exhibition — An adaptation of the albo-carbon burner to a table lamp- 

 stand.] Journ. Quck. Micr. Club, I. (1883) p. 197. 

 Hitchcock, R.— Instructions in Dry-plate Photography (in part). 



[" The object of these articles is to enable the reader to make good photo- 

 graphs with the ]\Iicroscojie, and to prepare lantern-transparencies for use 

 in illustrating articles read before Societies or public lectures," with " full 

 instructions for developing and finishing negatives, glass positives, and 

 paper prints."] 



Amcr. Mon. Micr. Journ., IV. (1883) pp. 84-8, 106-9. 

 Homogeneous-immersion Lenses. 



[The cement of Moller's slides shows no signs of deterioration from cedar 

 oil. Hollib' glue appears to be quite proof against the oil. Ward's brown 

 cement seems to be equally efficacious.] 



Micr. Nevs, III. (1883) p. 208. 

 Jadanza, N. — Sopra akuni sLstemi diotlrici composti di due lenti. (On some 

 dioptric systems composed of two lenses.) 



Atti R. Accad. Sei. Torino, XVIII. (1883) pp. 601-18 (5 figs.). 

 Johnson, G. C. — Photo-micrograpliy. 



["Since the introduction of lapid gelatine dry plates he showed that good 

 pictures might be obtained by the use of objectives of high power, such as 

 the l-16th in., even with onlinary gaslight."] 



Rep. and Froc. Alanch. Sci. Stud. Assoc, for 1882, p. 17. 



Jung, H.— Neuer Zeichenapparat (Embryograph) fiir schwache Vergrosserungen. 



(New Drawing Apparatus — Embryograph — for low amplifications.) l_Fost.'] 



Zcitschr. f. Instrumentenk., III. (1883) pp. 1G5-7 (2 figs.). 



M'Intosh, D. — United States Patent for a Microscope, No. 273752, 18tli June, 



1882 (title only). Zeitschr. f. Instrumentenk., III. (1883) Mai, Wrapper. 



Mauufacturers, Hints to. 



[Recommendation to " make stands that are adapted to the wants of students 

 rather than to attem])t to reform or educate the Harvard Medical College 

 professors " — where Hartnack Microscopes are almost universally em- 

 ployed — " ui) to an ajipreciatiou of the excellency of American stands and 

 costly objectives."] 



Amer. Mon. Micr. Journ., IV. (1883) pp. 97-8. 

 Mon OYER. — Formulea gc'ne'rales des systemes dioptriques centre's. ((General 

 foirardas for centred dioptric systems.) 



[Intended to show that for the formulaj of analytical geometry employed by 

 Gauss those cf eltmentary algebra may be substituted without at all 

 diminishing the exactness of the results.] 



Coinjites Rcndus, XCVII. (1883) pp. 88-91. 



