ANALYTICAL
30 A
ANNOUNCING
A NEW INSTRUMENT for research and routine
FOR EXACTING TECHNICAL APPLICATIONS VITREOSIL* (vitreous silica) tubing
POLAROGRAPHY
CHEMISTRY
possesses
many
characteristics you seek. A few of its properties are: Chemical a n d c a t a l y t i c inertness. Usefulness up to 1000°C a n d under ex treme thermal
shock.
Homogeneity and free dom from metallic impuri ties. Unusual electrical resistivity. Best ultra-violet transmission (in transmis
Instrument Designed to fill the growing need for a precise, reliable and stable manual polarographic instrument . . . will measure all the fundamental charac teristics of a dropping mercury electrode system (such as half-wave potentials and diffusion currents) in absolute terms and with high preci sion. Such a calibrated instrument is of utmost importance in routine work when complete waves are not obtained. It may also be used as an accurate potentiometer wherever an electrometer is not necessary. ONLY instrument with all these features : •
25 turn helical potentiometer ac curate to 0.1%, reading to one millivolt with a span voltage of 2.5 v. — and to double this value at a span voltage of 5.0 v.
•
Self-contained standard cell and standard resistors for calibrating. • Low resistance galvanometer with sensitivity approximating 0.005 microamperes per millimeter. Multiple shunt from 1 χ to 300 x. Scale length: 320 mm.
sion quality). USES Metals Alloyt Ores Plating solutions Boiler water Corrosion studies Paints Explosives Petroleums Gasoline Oils and soaps Sugar products Dyestufls Albumins Amino acids Alcohols
VITREOSIL tubing avail able promptly
from
stock in four qualities TRANSPARENT-SAND SURFACE GLAZED· SATIN SURFACE Stock sizes transparent up to 32 mm. bore, opaque to 4 bore.
Available
shipment.
Larger
for
promp'
diameter
can be supplied on spnin order. Can be had i n a l l nor m a l lengths. Send for Bulletin No. 9 for specified fions and prices.
Ketones Serums Proteins Alkaloids Blood Urtne Hormones Colloids Ktretics Reaction rates Equilibria Ca'aiysis Diffusion
For more information write for Bulletin 6 5 1 . Distributed by
General Scientific Equipment Co. Hamden 14
Connecticut
THE THERMAL SYNDICATE, LTD. 14 BIXLEY HEATH
LYNBROOK,
Ν. Υ.