334 



CENTRAL SCIENTIFIC CO., CHICAGO, U. S. A. 



No. 8342. 



No. 8344. 



No. 8346. 



No. 8348. 



No. 8306. 



No. F261. 



No. 8350. 



8296. LEVEL, Round, ' ' Which Way, ' ' of steel, nickel-plated. Diameter, 3.5 cm $0.90 



F261. LEVELING SCREWS, in sets of three, permitting the rapid leveling of board or glass plate. 

 Made entirely of metal, the base of which is accurately planed. Base japanned, screw white 



nickel-plated. Height, 7.5 cm; range of adjustment, 13 mm Pet set 1.65 



8306. LIBRARY PASTE, best grade. 



No A B 



Style Collapsible Tube 4-ounce Screw-Cap Jar 



Each .15 .15 



MAGNIFIERS 



8342. MAGNIFIERS, Doublet, consisting of two piano convex lenses in a metal mount, for use 

 either as a hand magnifier or in dissecting microscopes. 



No A B C 



Magnifying power, diameters 6 9 12 



Focal distance, mm 41.6 27.8 20.8 



Focal distance, inches 1.6 1.1 0.8 



Working distance, mm '. 22 15 12 



Diameter real field, mm 22 16 11 



Each 1.00 1.00 1.00 



8344. MAGNIFIER. Engravers' Glass, the standard magnifier for use in counting colonies of bacteria. 

 Magnifying power, 3.5 diameters. (See Public Health Report of the United States Public 

 Health 'Service Vol. XXX, No. 33, August 13, 1915) 1.00 



8346. MAGNIFIERS, Linen Testers, extensively used in elementary biology work, and for various 

 other purposes where a small compact magnifier is desired. Folds up into very small space. 



No A B 



Diameter of opening, inches V\ % 



Magnifying power, diameters 10 10 



Each 75 .75 



8348. MAGNIFIERS, Pocket, in folding mount of rubber and zylonite, very light and durable. 



No ABC 



Diameter of lens, mm 18 30 50 



Magnifying power, diameters 5 3.5 2 



Each ............ 50 .75 1.35 



8350. MAGNIFIERS, Pocket, same as No. 8348, but with double lens. 



No A B C 



Diameter of lenses, mm 15,20 25,30 37,44 



Magnifying power, diameters 5-12 3.5-8 2.5-5 



Each .'. 90 1.35 1.80 



8352. MAGNIFIERS, Pocket, same as No. 8350, but with triple lens. 



No A B 



Diameter of lenses, mm -12, 15, 18 15, 18, 20 



Magnifying power, diameters 7-30 4-20 



Each . 1.10 1.13 



