PIPETTE a n y reagent automatically
H e a t Exchange Tubing. A 4-page bulletin describes Calorex tubing. This heat exchange tubing m a d e of synthetic rubber is flat on one side for good con tact and can be used with various liq uids for t e m p e r a t u r e control from - 5 0 ° to + 1 2 0 ° C. Brinkmann, Cantiague Rd., W e s t b u r y , Ν . Υ. 11590.
617 Glass Specialty Items. An 8-page bulletin illustrates and decsribes an allglass water still, auto-pipet, D e w a r flask, soap-film flow meter, burets, and other special glass a p p a r a t u s m a d e by Houston Glass Fabricating Co. W. H . C u r t i n & Co., P . O. Box 1546, Houston, Texas. 77001. 618 Dielectric Data Instruments. Catalog W T W 1-E, 24 pages, describes and illus trates dielectric measuring instruments and measuring cells in addition to de scribing a constant t e m p e r a t u r e b a t h , a logarithmic indicator amplifier, and a signal generator. K a h l Scientific I n s t r u m e n t Corp., P . O. Box 1166, El Caj on, San Diego, Calif. 619
... continuously ...accurately The new MP-611 Microdyne® a u t o m a t i c pipette system is 100% complete . . . MO extra chambers to buy. W i t h j u s t one system you can deliver over 100 differ e n t volumes (from 0.1 to 10 m i l l i l i t r e s ) . Made completely of inert m a t e r i a l s ( P Y R E X * a n d T E F L O N * * ) . Simple t i t r a t i o n delivers precise d i s p e n s i n g of fluids to 0.05 ml. Available under General Services Ad ministration Federal Supply Service: FSC Group66, Part II. Item No.(s) 5i-2. The measuring pipette conforms in design in the specifications outlined in the National Bureau of Standards. Measuring and Serological uses con form in design with Federal Specifica tion D-D-v581a. The pipette conforms to the Class " A " tol erances prescribed in the National Bur eau Circular C-602.
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Available
Send for full details.
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with any
•Trademark Corning Glass
adapter.
"Trademark Dupont
International Applied Science Laboratory, Inc. 510 S o u t h F r a n k l i n S t r e e t H e m p s t e a d , N e w York Circle No. 66 on Readers' Service Card 122 A
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ANALYTICAL CHEMISTRY
DRUMMOND
MANUFACTURERS' LITERATURE
"MICROCAPS" (Disposable micro-pipettes) These pipettes consist of short lengths o f p r e cision m a d e c a p i l l a r y glass t u b i n g , c a l i b r a t e d t o contain a definite volume from end to end. They a r e accurate to within 1 % or less a n d a r e so low in cost that you can a f f o r d to use tbem once a n d discard them. W h i l e they a r e o f g r e a t value in g e n e r a l micro-chemical applications, they are especially useful in the handling o f dangerous material. No particular skill is needed in o r d e r to o b t a i n accurate results. " M i c r o c a p s " may be used in a number o f different ways. The most popular technique is as follows: the pipette is inserted through the rubber c a p on the end of the rubber bulb as sembly f a r enough to become visible through the glass tube. A hole in the rubber bulb permits f r e e cir culation o f air, so that the pipette may be filled by c a p i l lary attraction. When filled from end to e n d , the pipette contains the stated volume. To discharge: hold finger over the hole in the bulb and squeeze. To rinse, r e p e a t the c p e r a t i o n with the diluent. Another convenient method, when using pipettes of 20 lambdas capacity or l a r g e r , is to discard the bulb assembly and, holding the pipette with the fingers (or a p a i r o f tweez ers), fill it b y capillary attrac tion. Drop the p i p e t t e into a test tube containing the diluent a n d stopper. A short vigorous shaking will wash the contents o f the p i p e t t e into the diluent.
Galvanometers. " N o t e s on Moving Coil Galvanometers," 28 pages, de scribes t h e theory and application on galvanometers. T h e publication is use ful as a guide to the design, production, and application of galvanometers. Leeds & N o r t h r u p Co., 4901 Stenton Ave., Philadelphia 44, P a . 620
The bore in the tubing from which " M i c r o c a p s " a r e m a d e is so constant that the volume o f a p a r t i a l l y filled tube may be determined by simply calcu lating the volume p e r linear mm b y means of an o r d i n a r y metric scale. Example: Suppose a 5 0 l a m b d a pipette measures 1 0 0 mm in length; this means that each mm in length contains 0.5 lambdas. Therefore, should you find that the p a r t i a l volume measures 46mm in length, you would know that this volume equals 2 3 lambdas.
pH M e t e r s . A 12-page brochure de scribes and illustrates p H meters, elec trodes, titration techniques and acces sories, and calibration of instruments. K a h l Scientific I n s t r u m e n t Corp., P . O. Box 1166, El Caj on, San Diego, Calif.
621 G l a s s w a r e C l e a n i n g . Bulletin N o . 64 describes a u t o m a t e d laboratory glass ware cleaning procedures. T h e bulletin also describes new large volume con tinuous flow models of automatic L a b washers. T h e Chemical R u b b e r Co., 2310 Superior Ave. Cleveland 14, Ohio.
622 Portable Fume Hood. A 4-page b r o chure gives details a b o u t a new portable fiberglass fume hood for laboratories. Accessories are also discussed. L a b C o n Co, 8811 Prospect, K a n s a s City, M o . 64132. 623 Ultraviolet S p e c t r o p h o t o m e t e r Sam pler. Bulletin 7050, 2 pages, describes a sequential sampler for t h e Model D B ultraviolet spectrophotometer. This new accessory greatly speeds sample processing. Beckman, Scientific and Process I n s t r u m e n t s Division, 2500 H a r b o r Blvd., Fullerton, Calif. 92634.
624
Microcaps 1, 2 , 3, 4 , 5 , 100 lambda a b l e on short PRICES:
a r e stocked in the following sizes: 10, 1 5, 2 0 , 2 5 , 3 0 , 4 0 , 5 0 , 75 and capacity. Special sizes a r e a v a i l notice.
Sizes f r o m 1 t o 5 0 l a m b d a inclusive, $ 4 . 5 0 per vial o f 1 0 0 , including bulb assembly. Sizes over 5 0 to 1 0 0 l a m b d a s , $ 5 . 5 0 p e r vial o f 1 0 0 . Quantity discount: less o f 12 vials or more.
10%
in lots
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Made in U.S.A. by
DRUMMOND SCIENTIFIC CO. 5 0 0 Parkway B R O O M A L L , PA. Circle No. 43 on Readers' Service Card
