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Metallurgist at University of Notre Dame transcribes term- extensive studies of the grain growth which occurs duringperature data from four-point Speedomax Recorder con- annealing of aluminum and aluminum alloys, described innected to furnaces in foreground. Experiment is part of AIME, Metals Tech., September, 1947.

Test Data from Four Electric Furnaces

Recorded by Speedomax at Notre DameThe research shown above requires a recording

instrument which combines precision and highspeed. Several samples, usually four, are an-nealed simultaneously, with some heating cycleslasting only a few minutes. And yet the metal-lurgist requires complete temperature data fromeach sample.Speedomax multiple-point recorder does the

job well because:1) It records temperature of each sample everyfew seconds, so that the printed curve gives a

detailed record of temperature conditions at allfour points.2) Chart speed was specially selected for thisinstallation to give an easily-legible time scale.Speedomax and Micromax instruments are

available in a wide variety of ranges and speeds.One of the standai d models will provide a prac-tically "made-to-order" answer for any tempera-ture recording job which can be handled auto-matically. For specific information, write toLeeds & Northrup Co., 4926 Stenton Ave., Phila-delphia 44, Pa.

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The potentialities of this unique biochemical-prepared only by Ernst BischoffCompany, Inc.-can now be more thoroughly investigated. Our newly developedmethod permits increased production of exceptionally pure adenosine-5-phos-phoric acid and insures adequate supplies for pharmacological study and forfurther progress in bacteriological and biochemical research.

Adenosine-5-phosphoric acid, a purine nucleotide present in coenzymes Iand II and flavin dinucleotides, is intimately associated with life processes. Alsofundamental in phosphorylation reactions, this crucial compound is a vitalmetabolic link in energy transfer mechanisms like muscular contraction andother enzymic reactions.

Pharmacological reports indicate the applicability of MY-B-DEN to theproblems of vascular disturbances, cardiovascular malfunction and the degen-erative diseases. Its value in the treatment of these disorders is being elucidatedby further pharmacological research projects.

Summary of Data on a Typical Preparatiton of MY-B-DEN(Adenosine-5-Phosphoric Acid, Bischoff)

Source-Yeast fermentation procedures.How Supplied-Crystalline free acid.Formula-C10H14N507P * H20Purity-99.5%, based on adenine, ribose and phosphorus content.Molar Ratio-Adenine: ribose: phosphorus = 1.00: 1.01: 1.01.Position of phosphorus -Unequivocally on ribose in 5-position.Inorganic phosphorus -None present.

Complete analytical data, pertaining specifically to the individual MY-B-DEN preparationreleased, accompanies each shipment.The related compounds available are adenosine, guanosine and coenzyme I.

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Vol. 108 No. 2792 Friday, July 2, 1948

cONTENMFTS

The History and Ethics of the Use ofHuman Subjects in Medical Experi-ments. A. C. Ivy .

News and Notes .

Comments and Communications ...

Technical PapersCytogenetic Effects in Corn Exposed to AtomicBomb Ionizing Radiation at Bikini:L. F. Randolph, A. E. Longley, and

ChingHsiung Li .................................................................Crystalline Human Myoglobin: Some Physico-

chemical Properties and Chemical Compo-sition: Alessandro Rossi-Fanelli ..............................

Differential Effects of 2,4-D on Aerobic,Anaerobic, and Facultative AnaerobicMicroorganisms:Winfield A. Worth, Jr., and Anne M. McCabe

The Relative Sensitivities of Bacterial Virusesto Intense Sonic Vibration:Thomas F. Anderson, Shiela Boggs, and

B etty C.Winters .......................................................................

6 In the LaboratoryThree-dimensional Modeling of Cyclones in Ele-mentary Meteorology: Marshall Schalk ..........

10 Isolation of Crystalline DesoxyribonueleaseFromBeefPancreas: M. Kunitz ..............................

An Improved Method for Mounting SmallInsects:G. B. Fairchild and Marshall Hertig ..................

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Book ReviewsPlants and environment: a textbook of plant

autecology: R. F. Daubenmire.ReviewedbyPaul B. Sears ..................................

The corrosion handbook:Herbert H. Uhlig. (Ed.)Reviewed by Norman Hackerman ........................

Scientific Book Register.... 22

Science, a weekly journal, is published each Friday by theAmnerican Association for the Advancement of Science atThe Business Press, Incorporated, N. Queen St. and McGovernAve., Lancaster, Pa. Founded in 1880, it has been since1900 the official publication of the AAAS. Editorial and Ad-vertising Offices, 1515 Massachusetts Avenue, N.W.. Wash-ington 5, D. C. Telephone, EXecutive 6060 or 661. Cableaddress, SCIMAG, Washington. D. C. Entered as second-class matter at the Post Office at Lancaster, Pa., January 13,1948, under the Act of March 3, 1879. Acceptance for mail-ing at the special rate Postage provided for in the Act ofFebruary 28, 1925, embodled In paragraph 4, Sec. 538. P. L.and R., authorized January 13, 1948.

Articles offered for publication should be sent to the Edi-tor. The AAAS assumes no responsibility for the opinionsexpressed by contributors. Membership correspondence forthe AAAS should be sent to the Administrative Secretary.Annual subscription, $7.50; single copies, $25; foreign

postage (outside the Pan-American Union), $1.00 extra;

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Canadian postage, $.50- extra. Remittances and orders forsubscription and single copies should be sent to the Circula-tion Department, AS, North Queen Street and McGovernAvenue, Lancaster, Pennsylvania, and 1515 MassachusettsAvenue, N.W., Washington 5, D. C. Claims for missing num-bers will not be allowed if received more than 60 days fromdate of issue. No claims allowed from subscribers in CentralEurope, Asia, or the Pacific Islands other than Hawaii or be-cause of failure to notify the Circulation Department of achange of address or because copy is missing from the files.Change of address. Four weeks notice is required for

change of address. This should be sent to Science. 1515Massachusetts Avenue, N.W., Washington 5, D. C. Whenordering a change, please furnish an address stencil labelfrom a recent issue. Address changes can be made only if

the old as well as the new address is supplied.The American Association for the Advancement of Science

also publishes The Scientific Monthly. Subscription rateson request.

Mdrmd Atwood F. A. Moulton

Acting Editor Advertising Manager

Publications CommitteeFarrington Daniels, John E. In, ~Irtley F.

Mather, Walter B. Miles. Malcolm H. Soule.Steven M. Spencer

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JL1 4200-Brcroft-Warburg Apparatus, forfourteenmanometers, as described, with stirrer, twotable stands for seven manometers but with-out glassware, manometer supports, or ther-mometer. Inside dimensions of bath, I4' x291' X io' deep; over-all dimensions, i51/2'x 35½' X 273/4' high. For I5 volts, 6ocycles, AC or DC, each.......... $677.50

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MICRO LAMP, with Flask Condenser. Recommendedfor routine work requiring dark field illumination but adapt-able for bright field work by use of interchangeable bulbof lesser light intensity.

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6958C. Micro Lamp, with flask condenser. as above described, for dark field illumination. Complete with200-watt lamp bulb, etched glass plate, flask 300 ml and cork to fit. With 5 ft. rubber covered con-necting cord with snap switch and plug. For use on 115 volts, a.c. or d.. .20.10

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