The Ultimate in Weighing Precision: Blood Gas Accessory. Bulletin 7019, 4 pages, describes an accessory to the GC-2A gas chromatograph which can be used for the analyse of blood 0 2 , N 2 , CO, and C 0 2 . Only 0.1 cc. of blood is required and the analysis takes only 4 minutes. Beckman Scientific and Process Instruments Division, 2500 Harbor Blvd., Fullerton, Calif 607 Sodium Chloride Crystals. A 4-page bulletin discusses the use of sodium chloride crystals for infrared cell windows. The properties and the techniques for shaping, grinding, and polishing rocksalt crystals are described and illustrated. Optovac, Inc., North Brookfield, Mass. 608 Stable Isotopes of Oxygen. A 24page booklet details the availability of the stable isotopes of oxygen in various forms. Both O 17 and O 18 labeled compounds are presented. Included in the booklet are references to the use of these materials in different areas of analytical chemistry. YEDA Research and Development Co., Rehovoth, Israel. 609 Centrifuge Accessories. A 12-page catalog lists tubes, adapters, and accessories for the company's centrifuges. An illustrated index and pictorial charts aid in supplying information on the available products. Ivan Sorvall, Inc., Norwalk, Conn. 610
O.OOOOOOIg (0.1 Atg) with the
BUNGE " 2 5 U M "
ULTRA-MICRO BALANCE CAPACITY:
Safety Pipetters. A 4-page brochure describes the "Clinac" mechanical pipetter available in micro and standard sizes. These pipetters can deliver fractions of a drop with an accuracy of 0.01 ml. or better. Also pictured and described is the "Pumpett," which accommodates all sizes of pipettes. LaPine Scientific Co., 6001 South Knox Ave., Chicago 29, 111. 611 Chemicals. The 1963 British Drug House, Ltd., catalog lists 4000 packaged chemicals available from The Ealing Corp. Included are inorganics, microanalytical reagents, organic analytical standards, and materials for chromatography. The Ealing Corp., 2225 Massachusetts Ave., Cambridge 40, Mass. 6T2 Surface
Tension
Measurement.
"Techniques with the Cahn Electrobalance," No. 5 describes the use of the surface tension accessory to measure and record surface tension automatically. Cahn Instrument Co., 15505 Minnesota Ave., Paramount, Calif. 6 1 3 Fluorine Determination. Method Sheet No. 69 describes a direct spcctrophotometric procedure for the determination of fluoride ion. The absorb-
2 mg optical scale 9 mg automatic weight loader 2.5 g built-in tare weights 2.511 g Total
SENSITIVITY: 0.1 yug Estimations to ± O.OlVig
ILLUMINATION: An affixed temperature controlled tungsten light source evenly illuminates the read-out device
OUTSIDE LOADING: By automatic pan extraction through front panel
TEMPERATURE STABILITY: Triple housing of heavy guage metal and double heat absorbing glass
PRECISION
P F A L T Z
+
RELIABILITY
&
=
BUNGE
B A U E R , I N C .
153 WAVERLY PLACE, NEW YORK 14, NEW YORK · ALGONQUIN 5-0300 SCIENTIFIC INSTRUMENTS
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CHEMICALS
BIOLOGICAL STAINS · ESSENTIAL Circle No. 101 on Readers' Service Card
OILS
VOL. 35, NO. 11, OCTOBER 1963
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157 A
