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ANALYTICAL
CHEMISTRY
PETERSON·^ dgdgdgdgdgdgdgd dfggdgdgdgdgdfgdg gdgdrgddgddgdgdgd THE JACO PROJECTION COMPARATOR MICROPHOTOMETER for Speed and Accuracy in Quantitative Spectrochemical Analysis No longer must the practical spectrographer be uncertain as to the line he is actually reading. There is the line—in plain, full view—WHILE IT IS ACTUALLY BEING SCANNED. This is only one of the many features of this precision instrument which combines the qualities of improved reso lution, high speed, precise linear measurement, and wide density range into a practical device for fast, accurate quan titative analysis. O n c e again the JACO WAY is the fast, accurate, and convenient way.
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Ask for Technical Information Bulletin 1-4
JARRELL-ASH COMPANY 163 Newbury St.
Boston 1 6 , Mass.
"If it's an optical instrument think of J A R R E L L - A S H ! "
LEONARD P E T E R S O N & CO., INC. 1230 FULLERTON AVENUE
C H I C A G O 14. ILLINOIS
2 fine instruments in | MACBETH Titration-pH Meter T w o complete instruments in one, doing a w a y w i t h expensive duplications in laboratories where titrations a n d pH determinations are made. pH and titration sections have separate controls, assuring speed a n d accuracy. p H SECTION: Controls on left side of meter. Embodies the famous line operated, direct reading, continuous indicating Macbeth pH Meter. Scale of 0-14pH. TITRATION SECTION: Controls on right side of meter. Extremely flexible circuit w i t h continuously variable sensitivity. Meter range of a p p r o x i m a t e l y 2 4 0 m v to 3.7 ν permits large diversity of titration procedures. Bucking potentiometer a l l o w s adjusting potential be t w e e n plus 0.7Sv a n d minus 0.75v i n order t o shift scale to left or right, enlarging scope a n d sensitivity of meter. Titration section m a y be calibrated to read pH units or m i l l i v o l t values or if necessary it is possible to spread a narrow range of pH values over the entire scale. Polarized electrode systems are provided, permitting the user to do titrations such as water determinations using the Karl Fischer Reagent. Available in both 110 and 220 volt AC models. Price $210.00 complete.
M A C B E T H
C O R P O R A T I O N
2 2 7 W . 1 7 t h STREET, N E W Y O R K 1 1 , Ν . Υ .
