1 1 00 SUMMARY OF CURRENT RESEARCHES RELATING TO 



an expert preparer of elides, suggested that an arrangement for 

 illuminating the centro of slides would be of great convenience, and 

 the hollow spindlo in this turn-table is the result of the suggested 



Fig. 249 



Fig. 250 



need. A small mirror may be placed underneath and the light be 

 reflected through the spindle, or a lamp may be used for the same 

 purpose. 



