-
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
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Success is originality that didn't stop there:
Ace Mini-labIntroduced In 1950, it is the most complete,
best designed line of miniature glasswarel
The moment you start working with asimple flask or one of our
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0 blies, a fewv of which are showvn here, youwvill notice that
Ace Mini-Lab not onlytakes up less space, results in
considerable
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
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AC E GLa SS INCORPORATEDVineland,Now Jersey
LOUISVILLE, Ky. SPRINGFIELD, MASS.
SCIENCE, VOL. 149672
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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
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SCIENTIFIC AND PROCESSINSTRUMENTS DIVISIONFULLERTON, CALIFORNIA
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INTERNATIONAL SUBSIDIARIES: GENEVA, SWITZERLAND;
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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
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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