NEW BIOCHEMICAL REAGENTS

Tetranitro BT (TNBT)Dehydrogenose

Amino Acids

N,N-Dimethyl-1 -Naphthylamine.5-Sulfonyl Chloride

[Fluorescent protein analysis]

Sodium-6-Benzoyl-2-Naphthyl Phosphate,Sodium cx-Naphthyl Phosphate

Phosphatose

2-[41.Hydroxybenzeneazol Benzoic Acid(HABA)

Albumin in blood plasma

Carbonaphthoxy Choline IodideSerum choline esterase

6-Bromo-2-Naphthyl 3-D-Glucuronidef8-Glucuronidose

Plasma Aminopeptidass Activity Kit(7 components)

Tetrazolium SaltsRedox enzyme systems

Write for new catalog S122 today.Custom Syntheses Invited.

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Eyepieces: 5X (micro.), IOX (cross.)

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With artificial satellites already launched andspace travel almost a reality, astronomy hasbecome today's fastest growing hobby.Exploring the skies with a telescope is arelaxing diversion for father and son alike.UNITRON's handbook contains full-pageillustrated articles on astronomy, observing,telescopes and accessories. It is of interestto both beginners and advanced amateurs.

CONTENTS INCLUDE:Obsing the sun, mon, planets and wenders ef the skyConstelaUsn map * Hints for observers * Glossary of tdesopterms * Hew to cheese a tdescope * Astrophoetgraphy

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New ProductsThermocouple data logger (model

24271) will automatically scan, digitize,and record the outputs of up to 300chromel-alumel and iron-constantanthermocouples. Measurements are print-ed on paper tape and displayed on thereadout in four digits from +00.01 to+55.00 mv. This covers the usefulrange of chromel-alumel to 1375°C.Accuracy is said to be +25 ,uv and use-

ful sensitivity ±+10 juv. The system willtolerate a d-c common-mode voltage of150 volts and can also measure and re-

cord the common-mode voltage. Systemspeed is approximately 2 sec per ther-mocouple. Higher speeds and punched-tape or magnetic-tape recording are

available. The instrument is housed intwo consoles, one containing the ther-mocouple reference junctions, a cross-

bar scanner, and a differential analyzer.the other the control, measuring, andrecording equipment. The two can beseparated up to 150 ft.-J.s. (Non-Linear Systems, Inc., Dept. S535, DeiMar, Calif.)

Electronic counter (model 5243Lmeasures frequency, period, multiphperiod average, ratio, and multiples o

ratio. Time reference is provided by .proportional oven-controlled crystawith stability said to be ±3 parts ;I10' per day. The basic counter, withouplug-ins, offers a maximum countin-rate greater than 20 Mcy/sec with 8digit resolution. Plug-in units exten'frequency measurements to greater thai500 Mcy/sec. Display storage permitcontinuous display of the most recentlmeasured quantity even while countingthe display changes only if the measure

count changes. Sample rate is adjustablindependently of gate time. Operatintemperature range of the completelsolid-state instrument is -20° t+650C. Time base and function cor

trols are remotely programmable.-J.:(Hewlett-Packard Co., Dept. S537, 150Page Mill Rd., Palo Alto, Calif.)

The material in this section is prepared Ithe following contributing writers:

Robert L. Bowman (R.L.B.), LaboratoryTechnical Development, National Heart Instute, Bethesda 14, Md. (medical electronics ai

biomedical laboratory equipment).Joshua Stern (i.s.), Basic Instrumentation Se

tion, National Bureau of Standards, Washiniton 25, D.C. (physics, computing, electroni'and nuclear equipment).The information reported is obtained frc

manufacturers and other sources consideredliable. Neither Science nor any of the writeassumes responsibility for the accuracy of tinformation.Address inquiries to the manufacturer, me

tioning Science and the department number.

SCIENCE, VOL. I

SPORES-FERNSMICROSCOPIC ILLUSIONS

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*0-

MISTAIRE LABORATORIES152 Glen Ave.,Millburn, N.J.

'IN i

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RADARSCOPE RECORDING SYSTEMIN ONE-FIFTH CUBIC FOOT

The Electro-Optical Department of CSC hasdeveloped a Radarscope Recording Cam-era System that simultaneously photo-graphs radar images and records suchdata as time, range and directional orien-tation. CSC assumed responsibility forthe design and production of this systemfrom Bell & Howell Company about mid-way through the program.

Weighing less than 13 pounds, the systemuses a negative lens to photograph aradarscope through a port at the rearof the cathode ray tube. A data chamber,produces time-correlated information,reflected through a lens by two mirrors,for recording on the same frame of 35mm film. Careful design for field use;allows calibration and service without spe-cial tools. Assemblies can be removedeasily and replaced quickly.Electro-Optical, producing military andcommercial cameras, optical systems andprecision optics from conventional andexotic materials, is one of the divisions ofCSC. Others design and build systems*for analog and digital data handling, test-stand instrumentation and recording, pre-cision pressure measurement, telemetry,and industrial control. For details on appli-cations of custom systems in your areaof interest, call your nearest CSC regionaloffice or write:

CONSOLIDATED

Electron spin resonance spectrometer(model AL340SY) includes a master os-

cillator-detector-amplifier with regulatedpower supply, a 6-inch electromagnet, a

regulated magnet power supply, mag-

netic sweep unit, magnetic field mod-ulation units, and graphic recorder. Op-eration is set in the neighborhood of340 Mcy/sec but frequency may be ad-justed between 320 and 350 Mcy/sec.Sample size is 7 mm in diameter and10 mm long. Sensitivity is 10'4 spins per

gauss line width. Resolution is 1 partin 105. Magnetic field modulation fre-quency is 100 kcy/sec and the lock-indetector also operates at 100 kcy/ sec.

An auxiliary magnetic field modulatorat 60 cy/sec is also provided for oscil-loscope presentation of the ESR signals.The system is designed for operation on

a sturdy desk surface measuring 30 by60 inches. All units are air cooled. Op-erating temperature range is 0.3° to450°K.-J.s. (Alpha Scientific Labora-tories, Inc., Dept. S538, P.O. Box 333,Berkeley, Calif.)

Balance vector calculator simulatesand solves vector problems with slide-rule techniques. Angular differences as

well as proportional moment values are

readily visualized without plotting.

Phase angle changes during balancingprocedures, as well as moment changes,are read on transparent scales allowingsuperposition of the calculator on thedevice under study. Although the sliderule was developed for use with vibra-tion analyzers, its arbitrary scale valuespermit its use for solving other vectorproblems.-J.s. (Raydata Corp., Dept.S542, 1078 E. Granville Rd., Colum-bus 24, Ohio)

High-vacuum chamber (model CVU-18) offers an ultimate vacuum of 5 X

10-' torr and attains a vacuum of 2 X10' torr approximately 4 hours afterbakeout. The equipment combineschamber bakeout, baked sorbent trap-ping, water-cooled baffling, and diffu-sion pumping. The sorbent material can

FIELDRATEMETE

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Type N645 Field Ratemeter..........................................................

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* Transistorised battery-powered portableoflow weight.Waterproof case.

* Printed wiring technique.* Three ranges with integrating time

constants.* Suitable for use with G.M. tubes

or Scintillation Counter.

Associated detectors* Specially designed for measurement of

appropriate tolerance doses of ingestiblealpha, beta or gamma contamination.

Forfull information on the N645 Field Rate-meter or on any of the wide range of EkcoEquipment used in research, medicineand industry in more than 80 countries-write to

electronicsEKCO ELECTRONICS LTD-SOUTHEND-ON-SEA- ENGLAND

In U.S.A. contact associate companyAmerican Tradair Corporation

34-01 30th Street, Long Island City 6, New York

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CORPORATION1500 So. Shamrock Ave. * Monrovia, California14 DECEMBER 1962

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The ACTUAL LOT ANALYSISon 'BAKER ANALYZED' labelshelps you work faster withgreater precision.

Significant impurities are definedprecisely to the decimal ... you

achieve the required degree of accu-

racy immediately.

Almost 400 'Baker Analyzed' labelsalso bear the Actual Lot Assay (notmerely a range assay) as a furtheraid to accurate preparation of tracestandards. J. T. Baker Chemical Co.,Phillipsburg, N. J.

7 KEY REASONS TO USE'BAKER ANALYZED' REAGENTS

1. Highest standards of purity plusmost informative labeling.

2. ACTUAL LOT ANALYSIS on everylabel. ACTUAL LOT ASSAY on

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6. Quick deliveries from almost100 points of service.

7. Cap labels identify more than200 Baker Laboratory Chemicalsalso available for production use.

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J. T. BAKERLABORATORY CHEMICALS

1286

be replaced or regenerated and is saidto eliminate the need for a liquid-nitro-gen supply or other cryogenic equip-ment. The bell jar and pumping system

are contained in one unit and all vac-

uum gaging and control equipment are

located in a separate panel cabinet. Thestainless-steel bell jar is 18 inches indiameter by 30 inches high. It is raisedand lowered into position by a self-contained hydraulically controlled hoist.The jar-to-baseplate seal is made bymeans of a guard vacuum.-J.s. (Con-solidated Vacuum Corp., Dept. S534,1775 Mt. Read Blvd., Rochester 3,N.Y.)

Space simulation system includes bothnitrogen- and helium-cooled panels ar-

rayed to provide cold black walls andrapid cryogenic pumping to meet thethermal and ultra-high-vacuum require-ments of space simulation. Cryopump-ing in the 250-ft3 chamber achievespumping rates of more than 150,000lit./sec for nitrogen gas and 106 lit/secfor water vapor, both at 10 torr. Thesystem consists of a 7-ft-diameter, 9-ft-long stainless-steel chamber; 200-wattclosed-cycle helium refrigerator andcryopumping panels; nitrogen circu-lating system and black heat-sink ra-

diation-shield panels; and associatedvacuum pumps and instruments. Ulti-mate design pressure of the system isbelow 10-9 torr.-J.s. (Arthur D. Little,Inc., Dept. S536, Cambridge, Mass.)

The Rodolite aligning instrument con-

sists of two elements, a circular diffrac-tion grating in an adjustable mount anda sighting head. It is said to be capableof defining a straight line to within±0.0001 inches at 20 ft and to permiterrors of alignment to be readily de-termined. The target consists of a dif-fraction pattern of equally spaced brightand dark rings that remain in focuswithout adjustment at any separationfrom 6 inches to 20 ft. The line definedby the instrument is the normal throughthe center of th-e diffraction grating. Itis determined mechanically by observ-

In science -a notable variety

SARTON ON THEHISTORY OFSCIENCEEssays by George SartonReflecting Sarton's conceptthat the history of science isa core of truth unifying allknowledge this fascinating col-lection ranges from chapterson "Leonardo da Vinci" and"Maimonides"to "Iconograph-ic Honesty" and "notes on thereviewing of Learned Books."Editor, Dorothy Stirntson.

$7.50

THE DISCOVERYOF NEPTUNEby Morton GrosserThe dramatic scientific historyof two remarkable predictions,independently arrived at byLeverrier, a French astron-omer, and Adams, a mathema-tician at Cambridge and theinternational furor theytouched off. $4.95

ESSAY ONCLASSIFICATIONby Louis AgassizPublished two years before theOrigit of Species Agassiz'Essay gave classical biologyits most articulate expressionin the 19th century. Editor,Edward Ltric. John Harvard,Library. Belknap. $5.00

THE CONCEPTSAND THEORIESOF MODERNPHYSICSby J. B. StalloPropounding the relativity ofknowledge, this 19th centuryprophet denied the validity ofall absolute concepts. Editor,P. W. Bridgman. John Har-vard Library. Belknap. $4.75

ask youtr bookseller

ARVARD* U *UNIVERSITY PRESS

* Cambridge 38,* Massachusetts

S

SCIENCE, VOL. 13

I~~~~~~~~~~~~~~~~~~~~~~~~~~

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Model

X S2C0312e2

Model20729

High

Voltage

Supply

NUCLEAR

BUILDING

INSTRUMENTSSix Decade, 1 Mc Scaler, Model 20322-$550.00 Either 3 volt positive going,or 250 millivolt negative going pulsesfrom G-M detectors drive scaler. Countis continually displayed on front paneluntil preset state is reached and scalerstops. External clock or timing pulsescan be used to stop, start or reset scaler.Circuits are fully transistorized forreliability.High Voltage Power Supply, Model 20729-$175.00 Continuously variable pos-itive or negative potentials from 1360to 510 volts are set with coarse and finevoltage controls.

Panel lamps indicate polarity avail-able at rear BNC connectors. STAND-BY control removes high voltage fromconnector without disconnecting supply.Removable side panel provides completecircuit accessibility.Both power supply and scaler are pow-ered by separate plug-in low voltagesupply. Available in single module cab-inets or to fit into four-module cabinetcontaining compatible Building Blockinstruments to form a variety of instru-ment systems. For complete specifica-tions, write:

t tRADIATION COUNTER

LABORATORIES, INC.

5119 W. Grove St., Skokie, Ill.,U.S.A., Phone: YOrktown 6-8700

ing the diffraction pattern producedwhen the grating is illuminated. Thesighting head assembly consists of an

illuminator prism that carries projec-tion and reading graticules and is movedalong ball-bearing cross slides by two0.0001-inch drum micrometers. A fixed-focus microscope views the plane of thereading graticule. Measurements are

made by moving the illuminator prismon its coordinate cross slides until thediffraction pattern image is seen cen-

tered on the reading graticule. A modelcomprised of a mercury pool and a

transmission grating uses the same

sighting head to measure positions rela-tive to a vertical line. With this instru-ment, changes in level of ±0.05 sec ofarc are said to be measurable when thesighting head is 15 ft from the mercury

pool.-J.s. (Cooke, Troughton andSimms, Dept. S539, 91 Waite St.,Malden 48, Mass.)

Photoelectric titrator provides a lightsource, photocell, and galvanometersystem which can be adapted by theuse of suitable filters to monitor thechange in optical density at a specificwavelength, while titrant is beingadded to a reaction vessel. The endpoint of the reaction is determined bythe rapid change of optical densityand the quantity of reagent added isread from the burette. Samples of from2 to 40 ml can be handled while lightfrom an incandescent lamp, operatedfrom a stabilized power source, passes

through the magnetically stirred sampleand a suitable narrow-band color filterto a selenium barrier layer photocell.The output of the cell is indicated as

a projected hairline image on a 7-inch-long scale. Conventional burettes or

the Gelman microburet may be used.-R.L.B. (Gelman Instrument Co.,Dept. S523, 106 N. Main St., Chelsea,Mich.)

All solid-state statistical computer ac-

cepts relay closure or manual entries ofa statistical frequency distribution in up

to 10 cells with up to 99 entries per

cell. The computer instantly and con-

tinuously computes mean value andstandard deviation. Operation is com-

pletely automatic with correction ofcomputations made immediately witheach new entry. Optional input mecha-nisms permit manual or automaticsorting of input data. Automatic record-ing equipment for output signals isavailable.-J.s. (Boonshaft and Fuchs,Inc., Dept. S554, Hatboro IndustrialPark, Hatboro, Pa.)

CO LEMAN

Coleman precision nephelometersprovide accurate, reproduciblephotometric measurement of Tyn-dall effect-this permits specifica-tion of liquid clarity to :1=1% overthe range from absolute clarity tofaintly-visible haze.

This range is quantified by theColeman Nephelos Scale, the onenumerical notation system recog-nized throughout the world forexpressing liquid clarity.

In addition to clarity control,Coleman nephelometers permitaccurate measurement of minuteconcentrations of constituents insuspension . . . eliminate filtering,washing, drying and weighing.The Coleman Model 7 Photo-

Nephelometer is a single-purposeinstrument for measuring scatteredlight; the Model 9 Nepho-Color-imeter is a multi-purpose instru-ment combining the functions ofa nephelometer, colorimeter andturbidimeter.Ask for Bulletin SB-246 and

bibliography of nephelometricprocedures.-U

1287

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New Products

DOI: 10.1126/science.138.3546.1284 (3546), 1284-1287.138Science 

ARTICLE TOOLS http://science.sciencemag.org/content/138/3546/1284.citation

PERMISSIONS http://www.sciencemag.org/help/reprints-and-permissions

Terms of ServiceUse of this article is subject to the

trademark of AAAS. is a registeredScienceAdvancement of Science, 1200 New York Avenue NW, Washington, DC 20005. The title

(print ISSN 0036-8075; online ISSN 1095-9203) is published by the American Association for theScience

1962 by the American Association for the Advancement of Science

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