LOOK INTO THE

NEW LEITZ

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MICROSCOPE

It's new... modern ... up-to-the-minute! It's stream-lined ... sturdy ... packed with new features!One .., inclined binocular body tube and adjust-able interpupillary distance for more comfortableviewing.Two... new, improved prism system in stereo tubefor better image quality.Three. . . new rapid-changing device for threeobjectives.Four... objectives protected from damage by newtype mountings.Five. . . binocular body can be rotated through360 degrees for use with offset arm stand.

Six. . . redesigned bearing and special steel slid-ing surfaces insure long trouble-free performance.Seven. . . large, 60mm diameter mirror, adjust-able for any desired viewing effect.Eight. . . stand of new design with removablestage plate for examining specimens of all sizes.

Nine ... special reflected-light illuminators.

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GLUCURONOLACTONE-gamma lactoneof glucuronic acid-is synthesized fromD-glucose. This lactone, soluble inwater, slowly hydrolyses so that it is inequilibrium with the acid. Also avail-able are the sodium and potassium saltswhich are both supplied as stable,white, crystalline powders. All threederivatives from corn are now availablefor research or clinical investigations.Complete information will be sent on

INOSITOL-hexahydric alcohol of inter-est to biochemists-is a lipotropic agent

and one of the constituents of the vita-min B complex. Inositol is active incholesterol mobilization and in pre.

venting fatty infiltration of the liver.As a member of the vitamin B complex,it is necessary to the growth of certainanimals and microorganisms. A com-

prehensive booklet reviewing the liter-ature on the biochemistry of inositol;c Vit:v;lhh iinan r.am-at_

MEDICAL MYCOLOGY '

LABORATORY MANUALby MARGARET K. GRADY, University of Minnesota

This new laboratory manual presents com-plete methods and detailed diagrams forpreparing experiments in medical mycol-ogy. To simplify the identification ofactinomycetes, molds, yeasts and yeast-likeorganisms, laboratory instructions and per-tinent facts are repeated in each exercise.Copyright 1954; $2.25

LABORATORY MANUAL FORINTRODUCTORY MYCOLOGY

by CONSTANTINE J. ALEXOPOULOS andEVERETT S. BENEKE, Michigan State College

Recently published, this manual is especiallyvaluable for students who have completedone year of biological science with a goodunderstanding of biological principles.Through descriptions and illustrations ithelps them to systematize the fungi mostcommonly found and used for classroomstudy. Copyright 1953; $3.25Ordrthso manuals today...on approval if y wish...frm

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AO also makes abinocular body withparallel eyetubes for

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When using a binocular microscope your eyes are constantly shiftingfrom eyepieces to -wvorktable and back again. If the microscope hasparallel eyetubes your eyes must work to readjust themselves each time-now converging on the table at an angle of approximately 80, nowpointing parallel into tue eyetubes in order to fuse the two images.

To many people this is uncomfortable, tiring, and slows down thework -so AO optical scientists originated the familiar binocular bodywith converging eyetubes which is standard on AO Microscopes.

This example of AO Design Perfection is also apparent in the re-nowned AO Spencer Optics, dust-proof, dual-cone nosepiece, "pinch-grip" mechanical stage, "autofocus", custom tension adjustment, and

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