APPARA TUS FOR SCIENTIFIC DEMONSTRA TION 169 



then removed, when the lantern projects direct. Several of 

 these lanterns have reached England ; but there seems a 

 sort of national 'fashion' in apparatus, and so far as I am 

 aware, they are thought rather awkward in use by their pos- 

 sessors. 



Messrs, Newton & Co, have constructed a bi-unial lantern 



"\ !' ' \ir~n i 



;^i\ \ ii^y 



PIG. 92.-Newtons Vertical Bi-unial 



which produces vertical projections in another way, shown in 

 fig. 92. There are two separate lanterns, the top one so hinged 

 to the bottom one that the top lantern can be turned back in 

 a moment, so as to rest against stops and point vertically 



