618 



EECOED OF CURRENT RESEARCHES RELATING TO 



these is a catcli C, a piu from wliich projects through a slot in the 

 table, anrl is drawn towards the centre by a spring, shown dotted. 

 This I find acts admirably in every way, and provided the slide to be 



Fig. 1. 



re-ringed has been previously ringed in it, it will always go back truly 

 centered. The stops B B are placed in such a position that the centre 

 of the slide is a little out of truth with the centre of the table, and it 



is then seen in a moment, when a slide is placed in the clip, if the 

 right corners are engaged, and if not correct it only requires reversing 

 end for end. Glass cannot be held in a rigid grip, and I find the 



