Another "walk-away"

winner from

The "^L Model 55 AUTOMATIC PRINTOUT TITRATOR

Walking away from a task CAN mean getting it done— with Thomas "walk-away" products like the Model 55 Titrator, the kind of instruments that release an an­alyst from repetitive, mechanical chores—to do more important work.

The job here is to do 20 titrations as quickly as pos­sible, with high precision and absolute uniformity of endpcint.

Sample number and t i trat ion results issue on tape as shown above. The digital

register indicates the same informat ion for sample last t i trated and indicates

progress of the series.

The way to do it is to load the sample rack, push the button and walk away.

The Model 55 starts titrating Sample No. 1, and does not stop until it finishes Sample No. 20. All samples are titrated to same endpoint; within ±0.02 pH unit or ±0 .5 mv. Titrant volume for each sample is re­corded, with sample number, on paper tape printout. Volumes are printed to nearest 0.01 ml, between 00.00 and 09.99 ml, sample numbers as 3 digits be­tween 000 and 999.

The Model 55 uses 50 ml test tubes as titration vessels —they're cheaper, easier to clean and store than beakers. The high precision of the 10 ml buret saves expensive standardized reagents; you are now prob­ably using three times as much.

If you think you are locked-in on "standard" meth­ods, methods which specify sample volumes and titrant minima imposed by limitations of out-dated volumetric glassware and visual endpoint determina­t ion, we'l l be glad to show you how you can enjoy the benefits of our "walk-away" titrator without loss of analytical accuracy. Please ask us.

If you are wondering about cost, we think you'l l f ind that the price of the complete Model 55 Titrator is less than the annual cost of 50 manual titrations per day in your laboratory. Ask us about this, too.

ARTHUR H. THOMAS COMPANY • P.O. Box 779 • Philadelphia, Pa. 19105

CIRCLE 182 O N READER SERVICE CARD

92 A · ANALYTICAL CHEMISTRY, VOL. 44, NO. 3, MARCH 1972