766 



SUMMARY OF CURRENT IJKSKARCIIES RELATING TO 



ib recommended for beginners, as it practically removes all risk of 

 injury to objective and slide. Fig. 165 shows a non-inclinable form of 

 the same instrument. 



Fig. 1G5. 



Heusner's Object-stage with Exchangeable Plates.* — H. L. Hensner 

 has endeavoured to meet an inconvenience frequently experienced in 

 working with the ordinary vulcanite stage when a weakly coloured 

 preparation is apt to become invisible on the dark under-ground. 

 Although the operator may cover his stage with blotting-paper, the result 

 in many cases is unsatisfactory. The author has therefore arranged 

 with Messrs. Leitz so that the vulcanite stage can be replaced by a 



* Zeitschr. wiss. Mikrosk., xxv. (1903) pp. 62-4 (1 fig.). 



