444 



CENTRAL SCIENTIFIC CO., CHICAGO, U. 8. A. 



No. 12196. 



No. 12200. 



SLEEVES, see Aprons, Oversleeves and Laboratory Coats. 

 SLIDES, Microscopic, see Microscope Accessories. 

 SLIDE BOXES, see Microscope Accessories. 



12190. SLIDE RULE, Woodworth, a simple machine for multiplying and dividing. It is printed on 

 heavy bristol board, ready for the student to cut and fit together. Recommended by the Cen- 

 tral Association of Science and Mathematics Teachers Each $0.10 



Per dozen 1.00 



12192. SLIDE RULE, Mannheim, 10-inch, graduations on white paper, with a protective coating, 

 mounted on hardwood 1.40 



12194. SLIDE RULE, Mannheim, fine quality, 10-inch, in case with book of instructions 4.00 



12196. SLIDE RULE, Multiplex, 10-inch, useful in solving all arithmetical, trigonometrical, and log- 

 arithmetical problems which are possible with the Mannheim, and has also the following char- 

 acteristic advantages: Multiplication of three numbers in one setting; division of one number 

 by two numbers in one setting; more convenient solution of inverse proportion; direct solu- 

 tion in a single setting of a series of divisions with constant dividend; direct reading of cubes 

 and cube roots; direct reading of three-halves and two-thirds powers; direct solution in a 

 single setting of many combined operations. In case with book of instructions 6.25 



12200. SLIDE RULE, Chemists' Duplex, 10 inches in length, engine divided. The rule carries 138 

 chemical symbols which include the common acids, bases, salts, oxides, and elements em- 

 ployed by the average chemist. As each symbol has its individual position corresponding 

 to the logarithm of its molecular weight, the number of permutations and combinations pos- 

 sible covers the requirements of almost any problem. By using the logarithmic and cologarith- 

 mic scales in conjunction with the chemical gage points, problems in Stoichiometry, such as 

 Gravimetric Analysis, Volumetric Analysis, Equivalents, Percentage Composition, Conversion 

 Factors, Volume of Gas from a given weight of substance at different temperatures and pres- 

 sures, and many other analogous problems are readily solved. Aside from the solution of the 

 chemical problems above referred to any arithmetical problems solvable by logarithms are 

 readily and accurately done with a minimum number of settings. With glass indicator, in 

 morocco covered case with full directions 8.00 



SNIPS, Tinners', see Shears. 



12210. SOAP, Green Oil, U. S. P. Quality, a soft soap of potash base with strongly detergent properties. 

 Widely used for antiseptic purposes in connection with surgical and bacteriological work. 

 Useful for many purposes around the chemical laboratory, such as cleaning glass and porce- 

 lain, desk tops, sinks, stained hands, etc. In concentrated form, for solution in water. 



No A B C 



Style package jar can pail 



Weight, pounds 1 2 5 



Each 60 .95 1.90 



SOAP, Palm Oil, see No. 8952. 

 SODIUM SPOONS, see Spoons, Sodium. 



