55 A
VOLUME 25, NO. 11, NOVEMBER 1953
NYLAB
PREPARED CHEMICALLY W. & R. BALSTON, LTD. PAPER WHATMAN
GENUINE
Presents
FILTER
NEW
its * precision v o l t a g e stabilizer
PAPER
No.5
WHATMAN Filter Papers for Water Analysis
BUCTROHICAUy REGULATEO 6-VOLTS DC · RiGULATIOH ± 0.01% Designed especially for spectrophotometers ing the Beckman Model DU) and for general tory purposes.
(includ labora
• COMPLETELY REPLACES the corrosive non-sustain ing storage battery. • ELIMINATES periods of drifting, unnecessary de lays, and general nuisance. • ALWAYS READY for instant use with ordinary AC power lines.
WHATMAN Filter P a p e r No. 5 is the g r a d e most widely used in w a t e r analysis. No. 5 is a qualitative p a p e r that is very retentive and imparts a high polish to liquids filtered through it. No. 5 is used to remove every trace of cloudiness from samples b e fore determining phosphates colorimetrically. Other g r a d e s used in w a t e r analysis a r e No. 1 for the filtration of r e a g e n t s a n d the acid washed g r a d e s Nos. 4 0 , 4 1 , 41 -H, 4 2 and 4 4 for gravimetric analyses where the ash weight of the p a p e r is important.
DC OUTPUT FROM THE TWO MAIN (outside) Terminals: 5 . 5 - 6 . 5 volts, a d j u s t a b l e . 0 - 5 a m p e r e s ; or, after d i s c o n n e c t i n g t h e v o l t a g e divider, 0 - 6 a m p e r e s . FROM AN INTERMEDIATE TERMINAL (voltage divider): 2 . 0 volts, w h e n t h e main ferminpls a r e a t 6 . 0 volts. This is a factory setting i n t e n d e d for use with t h e DU S p e c t r o p h o t o m e t e r (current d r a i n u n d e r 0.1 a m p e r e ) . The v o l t a g e divider c a n b e r e s e t b y t h e user t o deliver a n y output within t h e r a n g e , 0 - 6 volts, a t currents u n d e r 1.0 a m p e r e .
ALL WHATMAN Filter P a p e r s a r e i m m e d i a t e l y a v a i l a b l e from all d e a l e r s in l a b o r a t o r y supplies but for samples or technical d a t a please write direct to us.
H. REEVE ANGEL & CO., INC. 52 Duane St. Remember
Dimensions: 1 7 " x l 3 " x l 0 " Weight: Approx. 5 0 lbs. N O . 8 0 7 1 0 Voltage Stabilizer . . . . Price—$375.00 Write for Bulletin
Papers
New York 7, Ν. Υ.
for Chromatography and
Cellulose
Powders
WHATMAN
Filter
are
must.
a
453.
• Parent Pending
NEW YORK Laboratory Supply NYLAB COMPANY INC.
KEY TO ALL LABORATORY SUPPLIES
7 6 V a r i c k S t r e e t , N e w York Telephone:
CAnal
1 3 , Ν. Υ.
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