L A B O R A T O R Y TRADE-MARK

1,2-DIMETHOXYETH ANE (Ethylene G lyco l Dimethyl Ether)

(peroxide inhibited)

ANHYDROUS! C H 3 O C H 2 C H 2 O C H 3

B.P. = 8 5 ° C Flash Ρ (open cup) = 4 0 ° F

In 5 gal . drums and in 1 and 5 lb . bottles. From stock or to order on short notice.

W r i t e to our Depf . "J" for Technical Data Sheet

C U S T O M SERVICES

W e s p e c i a l i z e in p r o d u c i n g o r g a n i c c o m p o u n d s , i n t e r m e d i a t e s ( u s e d i n m a k i n g h o r m o n e s , v i t a m i n s , e tc . ) a n d s e m i - f i n i s h e d d r u g s , insec t ic ides a n d . pes t ic ides o n a v o l u m e b a s i s :

Don' t spend for plant unless you are sure. It's better to hire us as many of our satisfied

customers do . Want their names?

ARAPAHOE CHEMICALS, INC. 2800 PEARL STREET · BOULDER. COLORADO PRODUCERS OF FINE ORGANIC C H E M I C A L S

1919—1960 La Motte Chemical

Chestertown Maryland U. S. A . Specialists in

Colorimetric Techniques Reagents—-Standards—Comparators

Send for Illustrated Controls Catalog Dept . A C

CLARK

MIGROANALYTICAL LABORATORY

CH, N , S, Halogen, Fluorine. Oxygen, Alkoxyl, Alklmide, Acetyl, Terminal Methyl, etc., by specialists In organic microchemical analysis.

Howard S. Clark, Director P. O. Box 17, Urbina, 111.—Telephone EMpire 7-8406

The Most Accurate Pipet

M I S C O Micro pipets make measurements reproducible t o 0 . 1 % routinely. Mos t com­plete line anywhere. Wri te for 12-page catalog.

MICROCHEMICAL SPECIALTIES CO. 182S Eastshore Highway, Berkeley 10, California

"STANDCO" VARIABLE SPEED

LABORATORY

STIRRER A precision made High Quality Stirrer with 2 Hollow Shafts.

Low Speed appro*. 18-270 RPM High Speed approx. 150-2250 RPM

With increased power at decreasing speeds.

Rugged and compact with many outstanding features

BULLETIN 7002

l ^<^w*^»^Λ^^»v^»^<^^« REAGENTS OF THE MONTH, ' < ^ v ^ « ^ « ^ ^ ^ v w ^ » v

a, α'-DIPYRIDYL NITROSO-R-SALT PICROLONIC ACID XYLENOL ORANGE

Over 3,000 other oiqanic laboratory chemicals in stock.

MASS SPECTROMETER

SERVICE

PETROLEUM ANALYTICAL RESEARCH CORP. P. O. Box 12334 Houston 17, Texas

Tel. Mission 9-2753

SPECIAL

LIGHT SOURCES by GATES

• Raymaster Biaekli{ht (long and short wave ultraviolet)

• Sodium Viper • Mercury Vapar • Zircanium Concentrated Arc Lamps • Mercury Point Sources • Imported Spectral Lamps • Photochemical or High Intensity "Uviarcs" • Auxiliary Operating Equipment for Above

Write* , o r F R E E Catalog or Contact π ι I I V y o u r Laboratory Supply Dealer

Analytical Grade Ion Exchange Resins?

(Prepared from Dowex Resins) ASK FOR PRICE LIST A M

ΛΒΙΟ-RAD Laboratories 32nd & GRIFFIN AVE. · RICHMOND, CALIFORNIA

SAFETY IGNITION UNIT SCH0NIGER OXYGEN FLASK THE F & M MODEL 141 SAFETY I G N I T I O N UNIT adds convenience to the Schôniger Oxygen Meth­od. The Method is use­fu l fo r c o n v e r t i n g or ­ganic carbon, halides including fluorides, sul­f u r , p h o s p h o r u s a n d various metals into a s o l u b l e o r g a n i c state in prepara­tion for final de­termination. WRITE FOR DESCRIPTIVE LITERATURE

HERMAN H.STKHT CO., INC.

2 7 PARK PLACE, NEW YORK 7 . N . Y .

F & M SCIENTIFIC CORP.

1202 ARNOLD AVE., N.C.C. AIR BASE NEW CASTLE, DEL. PHONE EA 8-6606

AIR POWERED STIRRERS For Laboratory Use

* H I G H T O R Q U E

* VARIABLE SPEEDS

* L I G H T W E I G H T

* DURABLE

* EXPLOSION PROOF

* Q U I E T

* COMPACT

* ECONOMICAL

See O u r Full Page A d in C H E M I C A L M A T E R I A L S C A T A L O G or Write /or Illustrated Literature . . . ARROW Engineering Co., Inc.

Ï 0 0 Central A v e . , H i l l s ide , N . J.

( A c i d W a s h e d )

FIREBRICK

FOR Chromatographic Ana lyzers

9 Mesh Sizes 20/40 to 180/200

LOCKWOOD & McLORIE, INC . Horsham, Pa.

LABORATORY SERVICES

«or the FOOD, FEED, DRUG a n d CHEMICAL INDUSTRIES

Analyses, Biological Evaluation, Toxicity Studies, Insecticide Testing

and Screening, Flavor Evaluation.

Project Research and Consultation

Wri te for Price Schedule P. O . Box 2217 · Madison 1 , Wis .

YOUR ANNOUNCEMENT of Equipment or Chemicals for Sale and/or Wanted, and Professional Services, can carry YOUR MESSAGE to the readers of the leading work-magazine for instru­m e n t a t i o n , c o n t r o l a n d analysis.

Rates on request

ANALYTICAL CHEMISTRY

Advertising Office

430 Park Avenue New York 22, Ν. Y.

1 1 0 A · ANALYTICAL CHEMISTRY

S U P P L Y C E N T E R

EASTERN CHEMICAL CORPORATION 34-K Spring Street Newark 4 , N. J.

GEORGEW.GATES&CO. Box 216., Franklin Square, L . I . . N . Y.