18 A A N A L Y T I C A L C H E M I S T R

A.H.T. CO. SPECIFICATION

R E S E R V O I R B U R E T T E S IN OUR STOCK FOR IMMEDIATE SHIPMENT

RESERVOIR BURETTES, A.H.T. Co. Speci­fication. Developed from the Knoefler and Squibb so-called "Automatic" burettes but of improved design and more rugged construction, embodying all the principal features of the earlier models and obviating the use of special clamps.

The delivery stopcocks are sufficiently ex­tended beyond the reservoir to permit convenient use with beakers or Erlenmeyer flasks up to 1000 ml capacity.

Burettes are 50 ml capacity, with all-round graduations, graduation interval 0.1 ml, and volume adjustment to ± 0.01 ml, which is equal to a percentage of error of 0.2%. The reservoir bottles are of Pyrex brand glass, 2000 ml capacity. The pressure bulbs are provided with an air vent in the connecting tube for convenient thumb control.

Burettes 2476-A, 2477-A and 2480-A are provided with automatic zero control and vent, i.e., with the diameter of the bore of the side filling tube such as to insure emptying of the internal zero control tip by capillarity.

2473-A.

2473-A. Burette, Reservoir, A.H.T. Co. Specification, with all-round graduations and open top. Capacity of burette 50 ml in l /10ths, ca­pacity of Pyrex brand glass reservoir 2000 ml. With rubber stopper connection. Complete with pressure bulb with air vent 19.95

2474-A. Ditto, but with Τ 34 interchangeable ground joint in place of rubber stopper connection with reservoir 21.40

2476-A. Burette, Reservoir, A.H.T. Co. Specification, identical with 2473-A but with all-round graduations and automatic zero device at top and syphon-type return for overflow. With rubber stopper connection.. . . 27.10

2477-A. Ditto, but with f" 34 interchangeable ground joint in place of rubber stopper connection with reservoir 28.80

2480-A. Burettes, Squibb's Improved Zero, A.H.T. Co. Specification, with interchangeable ground glass joints, including a non-freezing ball-and-socket joint No. 12/5 between the supply tube and the burette which main­tains an airtight connection but still allows a limited amount of movement at the joint, thus lessening the danger of accidental breakage. Complete with Pyrex brand glass reservoir, 2000 ml, with f 34 ground joint, spring-action pinch clamp for ball-and-socket joint, rubber pressure bulb with air vent for thumb control, and clamp with collar for supporting the burette at a dis­tance from the neck of the bottle. Capacity of burette, ml 25 50 Graduation interval, ml 1/10 1/10

Each , , 31.15 42.30

ARTHUR H. THOMAS COMPANY RETAIL — WHOLESALE — EXPORT

LABORATORY APPARATUS AND REAGENTS WEST WASHINGTON SQUARE, PHILADELPHIA 5, PA., U. S. A.

Cable Address "Balance ," Philadelphia