602 



SUMMARY OF CURRENT RESEARCHES RELATING TO 



introduced between the layers of drawing paper : it is then possible to 

 get three normal and three right for left drawings at one operation. 



Leppin and Masche's Mirrormegascope.* — The intention of the 



Fig. 67. 



3 \S 3 



Kondensator 



Objektiv 



-I 



Objekt 

 Fig. 68. 



designers was to produce an inexpensive portable apparatus for the pro- 

 jection of opaque objects (fig. 67). The light from a suitable strong 

 source falls on a mirror, silvered on face, set at 45° to the optical axis, 



Zeit. f. ang. Mikrosk. u. klin. Chemie, xii. (1906) pp. 1-5 (2 figs.). 



