OPTICAL INSTRUMENTS. 



175 



shell, many of which are highly ornamental, and may be 

 used with great advantage in public lectures for viewing 

 illustrations and experiments, as well as for the more com- 

 mon use at theatres. 



Price, in plain mounting (Fig. 6*75), $2.50. 



" ornamental, " (Fig. 676), $3.50 to ,155.00. 

 " " " with larger object glass, 87.00. 



Ivory and Gilt Mounted Opera Glass. (Fig. 677-.) 



Fig. 677. 



Price, $ 8.00. 



" large size, $10.00 and $12.00. 



Black Mounted Opera Glasses. (Fig. 678, next page.) 

 These are constructed of ivory, blacked and highly po- 

 lished, tortoise-shell, or metal japanned, either with the 

 tubes gilt or entirely black. 



Price, plain mounting japanned, $5.50 to $9.00. 

 " with best achromatic lenses, $9.00 and $10.00. 

 " white or black ivory, $13.00 and $16.00. 



" tortoise-shell, - " - $20.00 and 25.00. 



