tI 1

weigh 120 g 1200 g 1000 g 3000 g 10 kgunknowns +10 g tare +100 g tare +300 g tare +2500 g tare +3 kg tareto .. .

withprecision | 4- 0.5 mg _0.005 g '-0.05 g ±0.05 g ±0.5 gbetterthan ...

precision/capacity I part in I part in 1 part in I part in I part inrelationship 250,000 250,000 25,000 100,000 25,000of...

checkweigh +60 mg to +0.6 g to +5 g to +11 g to +50 g tooirectry to -60 mg of -0.6 g of -5 g of -11 g of -50 g ofover-undero target weight target weight target weight target weight target weightvalues from .....

weigh-into... 130 g 1300 g 1300 g 5500 g 13 kg(Including container)

batchweigh 130 g 1300 g 1300 g 5500 g 13 kgto...(Including container)

measuremass orforce belowthe balance

This is done by simply hanging a suspension device on the hook built into the bottom of thebalance. Weighing at some location vertically below the instrument is recommended for workwith corrosive, poisonous or radioactive substances in protective compartments, for weighingobjects in heating or drying ovens, or objects submerged in liquid.

P120 P1200 Pl 000 P3 P10

Success is originality that didn't stop there:

Ace Mini-labIntroduced In 1950, it is the most complete,

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The moment you start working with asimple flask or one of our popular assem-

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4> savings in reagent chemicals, but that thegood design makes Ace Mini-Lab a plea-sure to w?ork with.

Ace Mini-Lab is the first especially designed line ofminiature glassware. No simple reduction was employed:Our chemists and designers subjected each piece of glass-vare to practical experimentation until Mini-Lab per-formed with ease and efficiency. The popularity of AceMini-Lab attests to the success of their endeavors: Mini-Lab has been enthusiastically accepted in laboratories, inschools, everywhere.

Ace Mini-Lab is the most complete line of miniatureglassware. It can function as your complete laboratory. Newitems are constantly being added. 27 recent additions arefeatured in the Ace Mini-Lab brochure.

Ace Mini-Lab is versatile, comes in T 14/20, f 19/22,and 3 18/9 joints; a full line of components permits end-less variations. The excellent original design and versatilitywill make Ace Mini-Lab the most satisfactory miniatureglassware you have ever worked with. To check our com-plete selection, see your Ace Catalog 64 or send for Mini-Lab brochure.

AC E GLa SS INCORPORATEDVineland,Now Jersey

LOUISVILLE, Ky. SPRINGFIELD, MASS.

SCIENCE, VOL. 149672

Which

There are nineteen membersin the family of BeckmanReference Electrodes-just so youcan select the one best relatedto your requiremilents. There arefour different types of referencejunctions to pick from-asbestosfibre, palladium wire, groundglass sleeve, and porous frit. Eachcan be properly matched toyour specific application for highlyreliable determinations.In all, there are 121 Beckmanelectrodes iimmediately available.Call your local BeckmanSales Engineer or write for theElectrode Catalog.

INSTRUMENTS, INC.

SCIENTIFIC AND PROCESSINSTRUMENTS DIVISIONFULLERTON, CALIFORNIA .92634

INTERNATIONAL SUBSIDIARIES: GENEVA, SWITZERLAND;

MUNICH, GERMANY; GLENROTHES, SCOTLAND; PARIS,FRANCE; TOKYO, JAPAN; CAPETOWN, SOUTH AFRICA

708

. . .Rossi says that a working motheris a better example to her childrenthan one "who shelves her books alongwith her diploma." There are two fal-lacies in that statement. First, manyhomemakers read, participate in com-munity affairs, and retain a lively in-terest in the world. How many trulyeducated women shelve their booksand their intellectual curiosity? Second,Rossi ignores the contribution womencan make by showing their childrenhow to use leisure. Experts tell us thatone of the crises of the future will bethe growth of leisure and the inabilityto use it wisely. Surely an educatedmother who employs her educationconstructively while remaining at homecan teach her children, by example.that free time is a gift to becherished. ...

DOROTHY E. WYNNE165 Princeton Avenuie,Eggertsville, Newv York

The Critic Criticized

It is clear from his recent letter toScienice ( 1 6 July, p. 245) that all ofus have been taking Banesh Hoffmanmuch too seriously in his role as ob-jective test critic. His argument showsno trace of his scientific training.Briefly, it is this: he has raised certainobjections to the use of objective tests;Chauncey and Hilton state that theydo not have direct evidence that theseobjections are false: hence Hoffmanconcludes they are true. Note thatHoffman has no evidence to support hisarguments; they are entirely a prioriones. Note also that Chauncey andHilton have a good deal of indirectevidence, all of which hangs together,that the arguments are fallacious. Fora scientist it is surely a strange sort ofargument that the absence of directdata to the contrary proves that atheory is the correct one.

LLOYD G. HUMPHREYSDepartienit of P,sychology,Un iversity of 1llinois, Urbanta

Hoffman's letter indicates that he isinterested in statistical evidence andmay have some of his own. I shouldtherefore like to pose two questions forhim: (i) Just what kind of statisticalevidence would cause him to proclaimpublicly that his charges were indeedrefuted and that he had been wrong inhis evaluation of the best of the multi-ple-choice tests? (ii) What are the

magnitudes of the negative correlationsof "depth, subtlety, creativity, intellec-tual honesty, and superior knowledge"with Scholastic Aptitude Test scores?

JOHN E. MILHOLLANDDepartment of Psychology,University of Michiigan,Aniz Arbor

VA Hospitals:Length of Stay

In his argument concerning lengthof stay of patients in Veterans Admin-istration hospitals (Letters, 11 June,p. 141 1 ) Spratt overlooks these mostimportant points of difference between"private university hospitals" and thoseof the VA:

1) Patients discharged from surgicalwards in private hospitals are not al-ways ready to walk the streets upondischarge. The operation has been suc-cessful, but the recovery takes a longtime, and when the patient has runout of insurance mloney he prefers tohobble home rather than go bankruptat the rate of $30 a day. A VA hospital,by law, cannot discharge a patient un-til the patient is ready for discharge.

2) With the aging of the populationof veterans, disabling neurological dis-eases (such as strokes) are on the in-crease. Such illnesses are not like acuteappendicitis; the treatment is long, theprogress is slow, the complications fre-quent. A "private university hospital"uIsually shuLns this kind of patient aftera week or two of diagnostic work-up(which, again, takes up the largestchunk of insurance money, leavingthe rest for "chronic care" in somenursing home). Through no fault ofthe private hospital, to the patient itlooks as if once he has been squeezeddry of financial resources (usually in-surance) he is shipped somewhere else.One can imagine the howling in Con-gress if VA institutions were to followthis policy.

3) The VA carries on the most ex-tensive training program for medicalresidents, a benefit which may tend tolengthen hospital stay in some cases.

4) The VA is a very large organiza-tion; therefore anecdotes of particularinstances are bound to be misleading.The fact is that it provides the cheapesthigh-quality medical care in our country today.

J. M. SEGARRA71 Barnard Avenue,Watertowvn, Massachusetts

SCIENCE. VOL. 149

x I

EXPANSIONX2 X4

this one knobmay justify the entire

cost of the newGammascope H®e

Digital scale expansion provides resolutionequivalent to that of an 800-channel analyzerin any selected region of a spectrum.

It isn't easy to put a price tag on just one functionof an instrument. But if you've ever wanted to conducta particular experiment and found that the equipmentyou own doesn't have that capability, you know whatwe're driving at. That's why TMC crams so much ver-satility into every piece of equipment it produces. Wewant to cover your present needs, plus the inevitableexpansion.Take TMC's new Gammascope II, for instance. The

basic concept of the original Gammascope ... that ofa low-cost, self-contained, 100-channel pulse heightanalyzer ... has been retained. But into the compactnew Gammascope II has gone new output circuitry to

provide you with readout on virtually every type ofanalog and digital equipment ... new input circuitryfor multiscaling capability and analog sampling...and, of course, the digital scale expansion knob shownabove. But still that's only part of the story.

Coincidence and anti-coincidence capabilities, a de-pendent or independent single-channel analyzer anda linear CRT display (live or static) are all built-infeatures. Front panel threshold, upper lever, baselineand gain controls are also included. Count up all theknobs on a Gammascope II, and the capability theyrepresent, and we know you'll be convinced that it'sone of the soundest instrument investments you canmake today. For complete details, contact the nearestTMC office, or write: Nuclear Division, TechnicalMeasurement Corporation, 441 Washington Avenue,North Haven, Connecticut.

SCIENCE, VOL. 149712