CZAPSKI MICROSCOPE AND MODIFIED APPARATUS 45 



to what may always be a shifting object. Elaborate means of 

 mechanical adjustment could admittedly have their use for obser- 

 vation of non-living and still objects. For Zoological laboratory 

 work, e.g., the study of living transparent and translucent tissues 

 of lower types, it would obviously be desirable to have an apparatus 

 constructed and mounted so that the axis of illumination and 

 observation could be set in a vertical 

 plane at will, to permit of the study 

 of tissue media beneath the surface 

 of water or saline in a suitable 

 container ; and adjuncts readily 

 suggest themselves for providing 

 suitable stability and adaptability 

 for photographic work on still 

 objects. 



Fig. 13 represents Mayou's mount- 

 ing of a modified Gullstrand Slit- 

 lamp and Czapski microscope, made 

 by Messrs. Theodore Hamblin, Ltd. ; 

 and Fig. 14 represents Fincham's 

 pattern made by Messrs. Clement 

 Clarke & Co., Ltd. In the United 

 States of America a well-known 

 apparatus is made by the Bausch 

 and Lomb Optical Company. 



The subject of what can be done, 

 given a controllable and minute 

 illuminating beam, was left on 

 p. 39 and may now be resumed. Retroillumination (RI) has 

 been referred to (Figs. 5, 6, and 7), and whilst more will be 

 said of it (Figs. 35 to 42 et seq.) it will be best first to 

 describe other methods of illumination. When the beam is 

 very minute in diameter, particularly its antero-posterior oblique 

 diameter, i.e., in the direction of 0-VB (Fig. 15),^ it is 

 possible to illuminate directly, e.g., a precipitate on the 



Fig. 12. — Czapski Binocular 

 Microscope. 



1 In the use of anatomical terms here, it is assumed that the object — the 

 patient — is in the upright position, and that the axes of the illuminating 

 beam and microscope are set in the horizontal plane- 



