XXIII, 2. Neue Literatur. 247 



High -angle Condenser Carrior for petrological microscopes (Journ. R. 



Microsc. Soc. 190G, pt. 2, p. 223; vgl. W. Watson and Sons' Catalogue 



190G, p. 79). 

 MiLLEu's Sub-stage Spark-gap Lamp for the microscope (Journ. II. Microsc. 



Soc. 190<j, pt. 2, p. 223; vgl. Optical lustrument Monthly 19Ü5, no. 3, 



p. 13). 

 Nernst-Paul's Electric Science Lantern (Journ. R. Microsc. Soc. 190G, 



pt. 1, p. 97; vgl. R. W. Pauls Spezialkatalog 1905). 

 Nernst-Paul's high-power electric Projector Lamp (Journ. R. Microsc. Soc. 



1906, pt. 1, p. 97; vgl. R. W. Pauls Spezialkatalog 1905). 

 Nernst-Paul's optical electric Lantern (Journ. R. Microsc. Soc. 190G, pt. 1, 



p. 9G; vgl. R. W. Pauls Spezialkatalog 1905). 

 Optical Bench for Illumination with either ordinary or monochromatic 



Light (Journ. R. Microsc. Soc. 1906, pt. 2, p. 225). 



d. Ultramikroskop. 



Tswett, M., Zur Ultramikroskopie (Ber. d. d. botan. Ges. Bd. XXIV, 190G, 



p. 234; vgl. diese Zeitschr. Bd. XXIII, 190G, p. 199). 

 Wien, W. , Demonstration des Ultramikroskops (Sitzber. d. phys.-med. . 



Ges. Würzburg 1905, p. 31). 



e. Linsen. 



Beck's large Bull-Eye condensing Lens (Journ. R. Microsc. Soc. 1905, pt. 1, 



p. 99). 

 Howland's Instrument for centring, marking and testing lenses (Journ. R. 



Microsc. Soc. 190G, pt. 2, p. 221; vgl. Optical Instrument Monthly 1905, 



no. 3, p. 24). 



f. Verschiedenes. 



Croft , AV. B. , Some simple questions on the images of microscopes and 



telescopes (Phys. Soc. London, April 27, 190G ; vgl. Nature vol. LXXIV, 



190G, p. 71). 

 (Gordon, J. W. ,) Advances in Microscopy: The Microscope at Work 



(Journ. R. Microsc. Soc. 190G, pt. 2, p. 227; vgl. Lectures at the R. 



Institution, Febr. 1906). 



