60 SCIOPTICON MANUAL. 



fish, up and down is a matter of indifference; so that 

 inversion is no disadvantage. "With this tank for the 

 exhibition of living objects, chemical reactions, &c., a 

 large assortment of slides is less of a necessity. 



PRECAUTIONS ABOUT 



The lantern exhibition has to be conducted in so ob- 

 scure a light that the operator has to depend more on 

 the sense of feeling than sight; it is therefore important 

 that the slides should be in good condition and properly 

 arranged beforehand, and that their titles and descrip- 

 tions should be well fixed in memory, 



A convenient box for carrying the slides, for arrang- 

 ing them in, and for showing them from, is constructed 

 as follows.' Two boxes of any desirable length, 7J inches 

 wide and 4| inches deep, are hinged together, so that 

 each serves as a cover to the other. This double box 

 will hold the ordinary wooden mounted slides without 

 waste of room, and when open will show their labelled 

 edges in proper position and order. 



In social gatherings, the exhibitor is often urged to 

 bring out certain favorite pictures on call, which, in the 

 hurry and darkness, is apt to disarrange the slides, so 

 as to perplex the operator, and mar the beauty of the 

 entertainment. 



With careful management the box may close on prop- 

 erly arranged slides, at the close of the exhibition. 



