INDICATORS

Sixty-five Indicators through a range of PH values from

1

-0°2 to 130 can be supplied in solid form or in solution. The B.D.H. Universal Indicator has a range from 3.0 to IIo and shows the whole range of spectrum colours from red to violet in correct order.

The B.D.H. Universal Buffer Mixture is supplied in tubes each containing sufficient to make one litre of a buffer solution, from which solutions with PH from 2.7 to 11'4 may be made by the simple addition of 0.2N HCl or NaOH.

A copy of a special Price List of Indicators and the B.D.H. Chart of Hydrogen Ion Concentration Data will be supplied on application.

BPI

The British Drug Houses

Limited

London, N.1

An enlarged List of Boors' RESEARCH
CHEMICALS has been prepared because
of the rapid expansion of this impor-
tant side of our activities.

More than 1,000 Chemicals are in-
cluded, and over 80% of them are
made in our own laboratories.
Letters of appreciation received, and
the extension of our business, indicate
that the guaranteed purity of our pro-
ducts has become widely known.

FOR NEW LIST WRITE TO
WHOLESALE SALES DEPT.
BOOTS PURE DRUG
COMPANY LIMITED
MANUFACTURING CHEMISTS &
MAKERS OF FINE CHEMICALS
NOTTINGHAM ENGLAND