ANALYTICAL
32 A obtained in five different ranges extending from —40° to +400° F. The arched "bows" and flanged edges of the case provide the greatest possible angle of vision consistent with the best protection of the glass tube. The open spaces around the bulb ensure maximum air circulation for truevalue readings. A special feature of the thermometer is the removable scale and tube unit for easy replacement of a broken tube. This feature also permits the convenient interchange of various scales even though only one case is used. 15
MANUFACTURERS'
LITERATURE
Liquefier. Technical bulletin 20-A discusses the properties of Azite 900, a liquéfier which is of particular interest to manufacturers and converters of paper because of its capacity for reducing the viscosity of colloidal solutions of certain materials such as starches and proteins, its tendency to stabilize the viscosity of these same materials, its effect in retarding the growth of bacteria, and its ability to improve the heat stability or performance of acidic paper or paper exposed to acid conditions. Booklet is revision of one originally prepared in 1948. American Cyanamid Co. 16 Testing Instruments. A 32-page booklet gives details on recording gravitometers (with or without controller), dead weight gages, gas gravity balances, high pressure consistometers, moisture tester for gases, vapor pressure bombs, manometers, and thermometers. Refinery Supply Co. 17 Insulated Panels. New prefabricated insulated panels suitable for the erection of hot or cold walk-in rooms are subject of 2-page bulletin. Panels may be used in building rooms with controlled temperatures from —100° to +200° F. and relative humidities from 20 to 95%. Bowser Inc. 18 Laboratory Apparatus. New issue of company house organ, Precisionomics, describes automatic distillation apparatus, mercury relays, water baths, burners, heaters, stills, and a B.O.D. cabinet for low temperature testing of sewage and waste. Precision Scientific Co. 19 Electrochemical Measurements. Measurement of pH, oxidation-reduction potential, and electrolytic conductivity in industrial control systems is covered in 24-page bulletin. Fundamental principles of electrochemical measurements, as well as final control elements for automatic control systems, are outlined. Minneapolis-Honeywell Regulator Co. 20 pH Control. New 12-page catalog entitled "Precise pH Control and Water Tests" describes company's glass color standards, pocket and standard comparators, testers, replacement parts, and accessories. Hellige Inc. 21 Laboratory Equipment. Spring issue of Cenco News Chats describes laboratory trip scales, rain gages, centrifuges, temperature recorders, optical cells, sodium arc, immersion oils, and other apparatus. Central Scientific Co. 22 Resins for Adhesives. An 18-page booklet evaluates resins for use in rubber, cellulosic, and water-soluble adhesives. Properties are given for 17 resins. Acid number, bulking value, index of refraction, specific gravity, viscosity, and other properties are listed. Hercules Powder Co. 23 Analytical Balances. An 8-page pamphlet illustrates and describes analytical balances, Westphal specific gravity balance, and pan balances manufactured by Reyers and Zoon. Livingston Commercial Corp. 24 N e w Products. Publication gives details on helium and hydrogen liquefiers, oxygen plants, helium refrigerators, liquid oxygen pumps, low pressure gas holders, air coolers,
CHEMISTRY
and research electromagnets. Company's engineering, research, and development services are discussed. Arthur D. Little, Inc. 25 Infrared Microspectrometer. Spring issue of Instrument News features articles on infrared microspectrometer and new transverse panoramic camera. Perkin-Elmer Corp. 2 6 Hexachlorophene. Comprehensive bibliography on hexachlorophene contains abstracts of 51 scientific and trade articles and 19 patents. Compound is used as a germicide in soap and synthetic detergents. Sindar Corp. 27 Respirator. A 2-page bulletin CR-26 describes redesigned respirator featuring a new type of mineral wool filter which requires less than half the filter area and offers only half the breathing resistance of previous models having the same dust-collecting efficiency. The cushion-type face piece is soft and pliable and assures a gas-tight seal for a wide range of facial contours. Mine Safety Appliances Co. 28 Photochlorinations. An 8-page illustrated booklet provides information on photochlorinations and a proposed system for continuous-flow operation. Hanovia Chemical and Manufacturing Co. 29 Optical Parts. Lenses, prisms, reflectors, and miscellaneous optical parts are discussed in 16-page brochure. Crystal quartz lenses and condensers, as well as lenses, prisms, and plates of fused quartz, are described. Bausch & Lomb Optical Co. 30 Research Laboratory. The laboratory of the Aluminum Co. of America at East St. Louis, 111., is described in 14-page illustrated booklet, which also discusses the products that Aluminum Ore Co. provides for industry. Aluminum Co. of America. 31 Instrumentation. A nontechnical account of the role of instrumentation in everyday life is provided in 12-page pamphlet. Aviation, pasteurization, fire control, communication, and atomic energy are briefly covered. Weston Electrical Instrument Corp. 32 Chart Recorder. A 4-page bulletin explains how up to six permanent records of industrial processes may be obtained on a single strip chart recorder. The accuracy of the deflection-type measuring circuit and the simple chart-printing mechanism are described. An open view of the instrument illustrates the arrangement of the basic recorder assemblies. Wheelco Instruments Co. 33 Metallograph. Well-illustrated 20-page booklet covers the operation of the Balphot metallograph. The photographic unit, motor-driven carbon arc, ribbon filament, zirconium oxide concentrated arc, visual light source, filters, and MagnaViewer are discussed. Bausch & Lomb Optical Co. 34 Viscosity Measurement. New brochure describes instruments that provide an instantaneous method of measuring viscosity. Featured are the single-float, two-float, autosampling, cylindro-plunger, close-coupled, and remoterecording instruments. Fischer and Porter Co. 35 Shock Resistance. The basic concepts involved in designing for shock resistance are explained in comprehensive bulletin. The influence of weight, energy storage, stress concentration, and residual compressive stress is discussed, and information is given on means of preventing functional difficulties caused by shock. The Barry Corp. 36 Plastic Tubing. Pamphlet provides information on Alanol plastic tubing that is said to have a flex life 14 to 16 times that of rubber and may be used within a temperature range of —30° to +190° F . The tubing, available in sizes ranging from 0.12- to 1.0-inch inside diameter, is clear, nontoxic, and will withstand steam sterilization. Couse and Bolten Co. 37
