374 LENJ. PIKE'S, JR., DESCRIPTIVE CATALOGUE. 



Fig. 794. 



the powers of two lanterns, with only one small lamp of 

 intense brightness, free from the objectionable smell and 

 great heat of ordinary lamps, whereby a disc of twenty 

 feet for each tube may be obtained ; each disc is capable 

 of being darkened to any required extent, without the 

 least shadow on any particular portion of the picture ; 

 and, from the superiority in the optical arrangements of 

 the apparatus, each picture is perfectly flat and well de- 

 fined to the extreme edge. As the two discs may be 

 thrown either together on one circle, or two united at 

 various distances in length upon the screen, the number 

 of effects which may be produced may be easily imagined ; 

 they present a succession of dissolving views, so accurate- 

 ly and gradually dissolving, that the most experienced 

 eye can not perceive the process going on. The porta- 

 bility of the apparatus is also of importance; the whole 

 can be packed, viz., the lantern, gas-bag, retort, purifier, 



