THE RECO1

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APPARATUS

Applicable forclinical estimation of

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... for separations of organic orinorganic compounds havingelectro-migratory characteristicswhen electric potentialis applied.

PRICE: RECO Model E-800-2 Paper Electro-phoresis Apparatus, consisting of Power Unitand Migration Chamber, complete, $290.00

(Price does not include Automatic Timer)

SPECIAL FEATURES+ Water Cooled Surface for Paper or Starch.. .The plat-

form surface, on which buffer saturated filter paper orstarch is placed, is cooled by circulating water (see illus-tration) to reduce evaporation and minimize change inbuffer solution during operation, thus permitting use ofhigh voltages.

Foreign inquiries solicited. Delivered prices quoted on request.

IMANUFACTURED BYI RCH EQUIPMENT'U$ERCH EQUIPMENT

Power Unit supplies 0-720 volts at 200 miliamps con-tinuously variable, with 3lh-inch volt-meter and 3'A-inchdouble scale miliamp meter reading 0-20 and 0-200 mili-iamps for accurate current measurements. Direct currentmeasurements. Direct current ripple is reduced by meansof a choke-capacitor filter. Multiple power outlets avail-able at nominal extra cost. For 115 volts AC.

4 Anti-diffusion plates in electrode troughs reduce anychanges in electrolyte at the paper due to electrolysis.

± Platform surface is quickly adaptable for either paperor starch paste by means of end gates.

{ Electrode vessels easily dismounted for cleaning.+ Automatic timer for use in conjunction with power sup-

ply (at additional cost).Write for Brochure SS-10

CorporationCABINETS for ContinuousVertical Curtain Electrophor-esis Apparatus will be offeredshortly. If interested, requestBrochure S-12 to be mailedwhen issued.

RECO Paper Chromatographic Equipment alsoavairable: Chrornatocabs (for two-dimensional separ-ations) ... Drying Ovens. . . Electric Desalter (for removalof inorganic salts from organic and amino acids)... Racks,stainless steel and Pyrex (for one-dimensional separa-tions)...Pyrex Chromatography Jars (with specially groundtop edges)... Pyrex Solvent Troughs (or complete assem-blies)... Densitometers... Ultra Violet Lamps... Disc Cham-bers ... Stainless Steel Clips. . . Pyrex Indicator Sprayers... Micro Pipets. Write for General Catalog.

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NEW (2ND) EDITION - Conant et al.

Clinical MycologyThis useful manual gives a concise knowledge of thediagnosis and treatment of diseases of fungus origin.Including the latest advances, this New (2nd) Editiondefines each disease; tells where it is found;explains source of infection, symptoms,methods of laboratory examination; differentialdiagnosis; and how to institute treatment.All the most up-to-date developments are included.By NORMAN F. CONANT, Ph.D., Professor of Mycology and Associate Profes-sor of Bacteriology, Duke University School of Medicine; DAVID TILLERSONSMITH, M.D., Professor of Bacteriology and Associate Professor of Medicine,Duke University School of Medicine; RoGER DENIo BAKER, M.D., Chief,Laboratory Service Veterans Administration Hospital, Durham, N. C., andProfessor of Pathology, Duke University School of Medicine; JASPER LAMARCALLAWAY M.D. Professor of Dermatology and Syphilology Duke Univer-sity School of Iiedicine; and DONALD STOVER MARTIN, M.D.. Chief, Bac-teriology Section, Communicable Disease Center, Chamblee, Georgia. 456pages. 5ys" x 734", with 202 illustrations. $6.50. New (2nd) Edition.

NEW (6TH) EDITION - Harrow and Mazur's BiochemistryThis text will prove especially useful to instructor3 of college general biochemistry courses.Completely revised for its New (6th) Edition, it is a sound, authoritative presentation.Among the many new and expanded topics are paper chromatography, counter-current distribution,lipoproteins, criteria for the purity of a protein, quantitative estimation of amino acids,determination of "end groups" in a protein, the Donnan membrane equilibrium,techniques for demonstrating enzyme activity, and a new table of blood values.By BENJAMIN HmAmow, Ph.D., Professor of Chemistry, College of the City of New York; and ABRAHAM MAZUR, Ph.D., AssociateProfessor of Chemistry, College of the City of New York. 563 pages, 6" x 9", with 131 illustrations. New (6th) Edition-just Ready!

NEW - Walker's

Vertebrate DissectionThe aim of this manual is to help the student understandthe major anatomical transformations that have occurredin the vertebrates in the course of their evolution.The author has organized the book by systems.Under each he gives clear, descriptive guides to thedissection for several types representing the threelevels-primitive fish, terrestrial vertebrate, and mammal.The directions for dissection are accompanied bybrief discussions and by helpful illustrationsthe student would make himself in the laboratory.Teachers will find the material readily adaptable.By WARREN F. WALKER, JR., Ph.D., Associate Professor of Zoology, OberlinCollege, Oberlin, Ohio. About 320 pages, 6" x 9", illustrated. Just Ready.

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PHARMACOGNOSYLABOIRATORY MANUAL

by MAYNARD W. QUIMBY, RAYMOND W. VANDER WYK,WILLIAM E. HASSAN, JR.

Massachusetts College of Pharmacy

Designed specifically to acquaint studentswith the biological drugs and drug products,this new manual clearly outlines the moderndevelopments for their extraction and stand-ardization. Through studies of both usefuland harrmful constituents, students gain awell-grounded knowledge of this field inwhich scientists can now isolate potenttherapeutic drugs and administer them withminimal side effects. The official tests foridentity and purity discussed can be per-formed with ordinary laboratory equipment.Copyright 1953; $3.00

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