170 



BENJ. PIKE S, JR., DESCRIPTIVE CATALOGUE. 



is much preferable to those with round cases, being more 

 convenient to hold. They are made with one, two, and 

 three lenses. Those with three frames are usually' set with 

 one, one and a half, and two inch focus lenses ; they all turn 

 over each other and shut in the case, and are turned out at 

 pleasure. The three lenses singly, afford three magnifying 

 powers, and by combining two and two, we make three 

 more, and all three together, one more, making seven 

 different degrees of magnifying with the three glasses only. 

 Price, single lens magnifier, - $0.62. 



" " " larger size, $0.75. 



" double " - $1.00. 



" " " larger size, $1.12. 



" treble lens magnifier, $1.38. 



" " " larger size, $1.50. 



Fig. 663. 



Fig. 664. 



Watchmaker's Magnifier. (Fig 

 663.) The watch magnifier con 

 sisis of a convex lens of about 

 two inches focus, set in a deep 

 horn case, the larger end of which 

 is of such a size and form, as to 

 be held between the eyebrow and 

 bone of the cheek without incon- 

 venience. The cut represents the 

 size of the article. 



Price, 38 cts. 



Engraver's Magnifier. 

 (Fig. 664.) The- en- 

 graver's magnifier consists 

 of a convex lens, about 

 one and a half inches in 

 diameter and two inches 

 focus, set in a deep horn 

 case, which is usually sup- 

 ported over the work to 

 be engraved by a suitable 

 stand; the eye viewing 

 the work through the lens 

 while engraving. 



Price, 75 cts. 



