18A A N A L Y T I C A L C H E M I S T R Y

A.H.T. CO. SPECIFICATION

MAGNETIC STIRRING APPARATUS For variable speed stirring action wi th in either closed or open vessels

Round or half-round stirring bars, either sealed in Pyrex brand glass

or plastic coated

Separate rheostat for control at a distance of

approximately 30 inches

9235- R. Fig. 2. Fig. 1. Showing general stirring in a Showing stirring in electromctrio titrations

stoppered flask. with air and moisture excluded.

MAGNETIC STIRRING APPARATUS, A.H.T. Co. Specification. A compact, quiet-running apparatus which utilizes a rotating field of magnetic force to induce variable speed stirring action within either closed or open vessels. Stirring is accomplished by means of small magnetized bar A or B, which is placed in the liquid to be stirred and which is rotated by magnetic force applied below the container.

Consisting of a permanent bar magnet attached to the shaft of an electric motor and mounted in an aluminum housing with flat top 4J4 inches diameter and 4 ^ inches high. Can be used either on the table or on a support rod, attached by means of a clamp with swivel joint, Any type of vessel of glass, porcelain or non-magnetic metal, can be used, i.e.. flasks, beakers, culture dishes, crystalliz­ing dishes, evaporating dishes, test tubes, weighing bottles, etc. A ring-type burner is suitable when stirring at elevated temperatures. Suitable for any stirring operation which involves 1 ml to 1 liter of liquids with viscosities up to that of a 50% glycerol solution. Particularly convenient for use in closed systems. 9235-R. Stirring Apparatus, Magnetic, A.H.T. Co. Specification, as above described, with one each magnetized stir­

ring bars A (small, half-round, plastic coated) and Β (large, round, glass coated), Y% inch and 1% inches long, respectively; rheostat with graduated dial, 8-ft. connecting cord, and directions for use, but without glass vessel. For 115 volts, 50 or 60 cycles, a.c 38.50

9235-S. Ditto, but without stirring bars 33.40

9235-T5. Stirring Bars, Magnetized, Round, Glass Coated, consisting of a cylindrical permanent magnet sealed in Pyrex brand glass. Overall dimensions, inches Y% χ 9 / 3 2 1% χ % Each 2.65 2.90

9235-TJ. Stirring Bars, Magnetized, Half-Round, Plastic Coated, consisting of half-round permanent magnet with baked on lustrous black plastic coating which was developed to eliminate accidental breakage of glass-enclosed.bars. This plastic coating will withstand continuous use in boiling water and has good chemical resistance to weak or strong acids and alkalies except those with oxidizing properties such as nitric acid, alkaline peroxides, etc.; also resistant to organic solvents; overall width J^ inch, overall thickness % inch. Overall length, inches V% 1 % Each 2.55 2.95

9235-D5. Ditto, Round, Plastic Coated, generally similar to 9235-TJ, but with cylindrical permanent magnet. Overall dimensions, inches % χ Vaa XlA χ Υ% Each 2.65 2.90

10% discount in lots of IS or more, 9235-T5, 9283-U and 9SSÔ-U5, one size or assorted.

ARTHUR H. THOMAS COMPANY RETAIL—WHOLESALE—EXPORT

LABORATORY APPARATUS AND REAGENTS WEST WASHINGTON SQUARE, PHILADELPHIA 5, PA., U. S. A.

Cable Address "Balance," Philadelphia