VOLUME
37 A
2 0 , N O . 5, M A Y 1 9 4 8
INEXPENSIVE automatic BURETTES USEABLE WITH A N Y SIZE BOTTLE AVAILABLE WITH OR WITHOUT STOPCOCKS CHOICE OF T H R E E TYPES OF GLASS.
For all around convenience and economy, these SGA burettes are unequalled. Accurate within plus or minus 0.15 ml., they are just the thing for routine measurement of solutions and for student use. Use of a rubber stopper connection makes these burettes adaptable to any size bottle. They are filled by applying pressure to the rubber bulb, forcing the liquid up the center tube to overflow into the graduated column. When the pressure is released, the zero mark sets in automatically. All sizes are graduated in intervals of 1/10 ml. Select from the six variations to suit your needs, complete as illustrated, without bottle or rubber stopper.
J-835
J-835, Burette with stopcock, made of J-840, Burette with pinchcock, made of PYREX brand glass No. 774. PYREX brand glass No. 774. J-836, like J-835, but made of lime glass J-841, like J-840 but made of lime glass for alkali solutions. for alkali solutions.' J-837, like J-835, but made with Shellback J-842, like J-840 but made with Shellback glass. blue stripe glass for easy reading. Capacity 10 m l . 25 m l . 50 m l .
S.G.I A.CO.
J-835 $4.00 4.70 5.45.
G SCIENTIFIC S Co
G
J-836 $3.30 3.85 4.70
J-837 $3.75 4.15 5.15
J-840 $3.00 3.70 4.35
J-841 $2.50 3.05 3.60
J-842 $2.60 3.20 3.90
J-840
GLASS APPAATUS CO. INC BLOOFIELD -
LABORATORY APPARATUS - INSTRUMENTS - CHEMICALS - GLA
WELCH
SPECTROMETER
with A N G S T R O M and DEGREE SCALES Gross-Hair Illuminator available
a new development . • • •
. . in spectrometers accurate · versatile easily operated economical to own
No. 3692
• adjustable micromotion slit • fine adjustment tangent screw • locking device This is a splendid elementary spectrometer. It is convenient and is sufficiently rugged to be used by students who are being introduced to spectrometric methods of analysis. The unique Angstrom scale is a timesaver. It is a valuable teaching instrument.
PRICE $100 00 witTKsm
W. M. W e l c h
CROSS-HAIR ILLUMINATOR $ a i iona
1515 Sedgwick St., Dept. A
Scientific Established 1880
Company
Chicago 10, Illinois, U. S. A.