now... contamination-free pumping plus cool, noiseless operation!
ADVANCED MODEL
varistaltic pump
®
Produces peristaltic effect to pump acids, bases, toxic and sterile liquids and gases—safely and quietly through flexible tubing — without the liquid coming in contact with pumping mechanism. Gearless direct-drive permanent-magnet motor is solid-state controlled . . . for reproducibly adjusted speeds from 24 to 400 R.P.M., with ± 3 % stability . . . and a delivery volume range from 50 ml to 5,000 ml per minute. Switch action reversibility. Unit weighs approx. 18 lbs., is housed in handsome 2-tone lightweight metal cabinet—12 1 /2" longx9 1 /2" deepx7 1 /2" high. Available in 115-volt or 220-volt A.C. models. Advanced Model Varistaltic Pump (115-volt A.C.) $210.00 For information on our full line of Varistaltic Pumps-Rheostat Controlled, Generator Feed-Back Controlled, Solid State and Air Driven Explosion Proof Model, write for Complete Bulletin. Available through your laboratory supply dealers
MANOSTAT Corporation 2 0 N . Moore St., Dept. 5 2 1 , N.Y., N.Y.
10013
Manufacturers' Literature EPR Spectrometer Systems. Control console modules, the microwave bridge, magnet systems, cavities, accessories, and performance and physical specifications for the E-line electron paramagnetic resonance spectrometer systems are described in a 12-page brochure. Varian, Analytical Instrument Division, 611 Hansen Way, Palo Alto, Calif. 94303 623 Acid Digestion Bomb. Product Sheet 4745 presents a Teflon (Du Pont) lined bomb for dissolving silicates and other refractory materials in strong acids. Parr Instrument Co., Inc., 211 Fiftythird St., Moline, 111. 61265 624 Multichannel Analyzer. Bulletin 900P, 12 pages, describes the 900 Series multichannel analyzers which feature builtin optional functions and accessories. Packard Instrument Co., Inc., 2200 Warrenville Rd., Downers Grove, 111. 60515 625 Company Periodicals Requests for copies of the following publications, catalogs, etc., should be sent directly to the address shown. Business or professional letterheads are requested.
Circle No. 110 on Readers' Service Card
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NEW
The Laboratory, Vol. 37, No. 1. Among the new instruments discussed in this issue is a desk-size direct-reading spectrometer for multi-element analysis. Fisher Scientific Co., 312 Fisher Bldg., Pittsburgh, Pa. 15219
BETHLEHEM GLASS TUBING SCORER! A radical departure from the conventionally designed glass knife. For scoring borosilicate glass tubing. T h e handle is of solid clear plastic. A tungsten carbide cutting blade, triangular in design with three cutting edges is inserted and clamped into the handle. T h e blade is reversible a n d actually provides six usable cutting edges in all. Blades are replaceable. Cutting edge IV2"—overall length 6"— shipping weight 1 lb. K N 3 Knife $24.00
BETHLEHEM APPARATUS C O M P A N Y , INC. Hellertown, Pa. 18055
Phone 215 838-7034
Circle No. 16 on Readers' Service Card
122 A •
ANALYTICAL CHEMISTRY
Laboratory Instrument Mart, April/ May 1969. Spectrophotometers, gas chromatographs, oscilloscopes, and computers are among the instruments listed. Included are tips on how the items may be bought, sold, traded, and leased. Laboratory Instrument Exchange, Inc., 301 E. Erie St., Chicago, 111. 60611 Current Laboratory Practice, Vol. 1, No. 2. A method for separating DNP amino acids in urine and serum is offered in this issue. Gelman Instrument Co., P. O. Box 1448, Ann Arbor, Mich. 48106 Givaudanian, April 1969. The physical and chemical testing of aerosol cosmetics is discussed in this issue. Givaudan Corp., 321 W. 44 St., New York, N. Y. 10036 Gas-Chrom Newsletter, Vol. 10, No. 2. A list of basic columns for several areas of gas chromatographic analysis is offered. Applied Science Laboratories, Inc., State College, Pa. 16801
