ANALYTICAL
34A for maintenance and providing a minimum of "downtime." The heater is certified to meet FCC regulations. In addition to water cooling, blowers recirculate air within the enclosure to cool the seals of the oscillator tube and the bases of the rectifier tubes. Oscillator, control, and rectifier panel, as well as other components, are located within the cabinet in order to be easily accessible for maintenance. Long-scale, switchboard-type instruments provide improved readability, enabling the operator to determine operating characteristics quickly and accurately. The heater can be used for long- or short-run production, and is available in two models—with or without variable power adjustment. For the short-run production of a wide variety of parts, GE recommends the Type HM-20L1 heater. This model has a variable power adjustment from 0 to 100% by means of a rheostat, either mounted in the work table or purchased separately for mounting elsewhere. The versatility of this unit enables the operator to perform rapid on-off heater operation to harden selected areas accurately in less time. For long-run, higher-production applications which do not have rapid cycling, the Type HM-20L2 heater (without variable power adjustment) is recommended. On such applications, the heater is initially set to heat a specific part and no further adjustment is necessary. The complete heater, in either model, weighs approximately 3600 pounds. Units are available for operation on 230-, 460-, or 550-volt, three-phase, 60-cycle power supplies. 16 Manometer Calibrator E. Machlett & Son offers a new instrument for the calibration of Warburg constant-volume manometers. The device is said to simplify and shorten the calibration procedure by eliminating the handling and weighing of mercury. Each division of the micrometer scale of the calibrator represents a volume displacement of 0.001 ml. The calibrator can be used wherever extreme accuracy is required to determine fluid or gas volume displacement, as in the case of pipets, microburets, and similar apparatus. 17
MANUFACTURERS'
LITERATURE
Dynel. An 8-page pamphlet describes properties of dynel: tenacity, elongation, stiffness, toughness, flammability, moisture regain, light stability, and resistance to water, chemicals, insects, and mildew. Information on price and standard sizes and lengths of dynel staple is also included. Carbide and Carbon Chemicals Division. 18 Silica Aerogel. Applications of Santocel C, a finely divided, pure white silica aerogel, are described in new 16-page booklet. Typical grinding and reducing procedures for oleoresinous and alkyd flat coatings are explained. Product is used in flat and semigloss varnishes, as well as in lacquers, plastisols, organosols, and free films. Merrimac Division. 19 Apparatus. Current issue of Better Analysis presents articles on flame photometer, grating monochromator, and micromulls. Baird Associates, Inc. 20
CHEMISTRY
Potentiometers. Catalog 15-15, well illustrated with photographs and drawings, gives information on potentiometers, strip chart controllers and recorders, circular chart controllers and recorders, switches, thermocouples, motors, and motorized valves. Minneapolis-Honeywell Regulator Co. 23 Bismuth Wire. New 20-page booklet discusses ductile bismuth wire and ribbon. Description of electrical properties and list of references are included. Fitzpatrick Electric Supply Co. 24 Peracetic Acid. "Peracetic Acid, A New BactericideFungicide" is title of 21-page bulletin which covers general properties of product, bactericidal properties, equipment sanitization, enzyme inactivation, toxicity, analysis, and suggested applications in the food industry. Buffalo ElectroChemical Co. 25 Organic Chemicals. Attractive, well illustrated, 32-page catalog gives physical properties, uses, and container specifications for aliphatic chemicals (acids, anhydrides, alcohols, aldehydes, plasticizers, and solvents), aromatic chemicals (amines, aminophenols, phenols, and phenol ethers), cellulose products, and inorganic chemicals. Tennessee Eastman Co. 26 Nichrome Wire. Information on Nichrome and other highnickel heat- and corrosion-resistant alloys is given in 75-page publication. Creep data, heating element data, life expectancy, temperature resistance, weights, wire data, strip data, and other details are included. Driver-Harris Co. 27 Water Softeners. A 115-page book describes polyamino acids and salts (Versenes) employed as water softeners. Sections cover general information, applications, toxicity, and analytical methods (microanalysis, water hardness determination by Versenate method, and analysis of Versene in soap). Bersworth Chemical Co. 28 Wave Analyzer. A 4-page bulletin describes analyzer that has been designed primarily for analysis of complex vibration wave forms, but is equally applicable to the measurement of audio and power frequency wave forms up to 21 kilocycles per second. Muirhead & Co., Ltd. 29 Time Interval Meter. Pamphlet outlines basic design, operation, specifications, and applications of time interval meter which provides a direct reading of elapsed time between any two events in the range of 10 microseconds to 1 second. Accuracy of measurement is ±10 microseconds. Berkeley Scientific Corp. 30 Methoxychlor Determinations. Laboratory procedures for methoxychlor determinations are described in technical bulletin. Procedure can be used to distinguish amount of compound in spray residues on crops, as well as deposits in milk or in the tissues of meat. E. I. du Pont de Nemours & Co. 31 Thermoregulators and Thermostats. Well illustrated with photographs and cutaway drawings, 12-page catalog discusses mercury-activated thermoregulators and thermostats, which may be selected according to accuracy requirements from ±0.005° to ±0.10° C. H-B Instrument Co. 32
o-Nitrobiphenyl. Technical Bulletin O-D-102 on o-nitrobiphenyl gives physical and chemical properties, plasticizing and fungicidal characteristics, toxicity, and suggested uses. Monsanto Chemical Co. 21
Spectrographic Outfits. A 12-page illustrated brochure describes automatic large {FD 170 cm.), medium {FD 60 cm.), and intermediate and small quartz spectrographs {FD 38 and 20 cm.). Any one or more of these instruments may be used in analysis of steels, heavy metals, aluminum and other nonferrous alloys, alkalies, or biological samples. Jarrell-Ash Co; 33
Humidity Control. A 4-page bulletin describes the Kathabar system of humidity control, which combines chemical dëhumidification with mechanical refrigeration to obtain air of low dew point. Air a t subzero temperatures can be produced without formation of frost on the cooling coils. Surface Combustion Corp. 22
Laboratory Equipment. A 28-page booklet entitled "What's New for the Laboratory?" describes tumbler-mixer, glass solvent trough for use in paper chromatography, viscometer, pyrometer, mercury filter, Geiger counters, Van Slyke blood gas apparatus, and other laboratory equipment. Scientific Glass Apparatus Co. 34
