Sunday 17 April 2022

POLAROGRAPH: Device that Analyses Liquors

 CAPE TIMES - 1933, August 19

Revealing Chemical Contents

Whenever liquors fall under the suspicion of not being what they are claimed to be, the use of an electrical device called a polarograph, which was invented in 1922 by Prof. Jarslav Heyrovsky of Charles University, Prague, will establish beyond doubt their guilt or innocence.
The Polarograph automatically analyses all kinds of liquids and solids, including the most complex chemical solutions, and thus saves hours of tedious work in laboratories. The solution to be analyzed is placed in a small container, in which it is electrolytically decomposed. Then by closing an electric switch the device automatically records on a strip of paper wound on a drum a graph in the form of a curved line which indicates both the relationship between the current passing through the solution and the magnitude of the electromotive force.

In this way both the kind and the amount of chemical substances present in the liquor are revealed in four or five minutes. This saves hours of time necessary when the slower and longer laboratory methods of making such analyses are used. Other advantages to be gained by the use of the polarograph, as Prof. Heyrovsky points out, are greater precision, greater accuracy for microanalysis, simultaneous quantitative and qualitative analysis, the total absence of any effect on the solution and the consequent ability to repeat the analysis indefinitely.

Prof. Heyrovsky says that the use of the polarograph makes it possible for the investigator to analyze both qualitatively and quantitatively the numerous complex alcohols as well as the still more complicated compounds of which the lowest forms of life are composed.

“The polarograph method in the determination of substances occurring in almost imperceptible traces,” Prof. Heyrovsky explains, “is more than 1 000 times as sensitive as X-ray spectrum analysis. 

The presence of so infinitesimal a quantity as one ten-thousandth of a part of many substances, though not all, may be detected.

“This instrument also may be used in research laboratories in physics, chemistry, biology, in clinics, medical laboratories, laboratories of the petroleum and other industries, and in pharmaceutical research. In industry it can be used in the study of fermentation processes, for the determination of the quality of molasses and of various sugar, and in the study of ores and alloys, rocks, waters, gases, minerals and meteorites.”

Read more about the POLAROGRAPH at

No comments:

Post a Comment

Cape Town’s new £22 000 Broadcasting Station at Milnerton

 CAPE TIMES - 1933, July 18 The Cape and Peninsula Broadcasting Association started Cape Town’s first Broadcasting Station on September 15, ...