Modern Objectivity in Analysis
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T-. Churchill’s address, delivered at the dinner held in conjunction with the Third Annual Analytical Symposium of the Division of Analytical Chemistry of the Pittsburgh A.C.S. Section, provided two striking examples of the evolutionary changes which instrumentation has wrought in the work of the chemical analyst and illustrated the delicate sensitivity of modern physicochemical devices now available in the field of analytical chemistry. Speaking first of control work on aluminum alloys, bIr. Churchill pointed out that many remelting furnaces haye a capacity of 35,000 pounds. From this molten metal, a sample is poured having a weight of about 60 grams. This is a sampling ratio of 1 to 260,000. When the spectrographer sparks this sample, he actually uses or consumes but 1 mg. of metal; so the ratio of sample to original material becomes 1 to 1,500,000,000. When the sample is sparked, radiation occurs, and of the total light emitted, only 30 billionths is introduced into the spectrograph and the sample fraction becomes one to 45 quadrillion or 1 to 4 X 10”. In another example the chief of the Analytical Division of the Aluminum Company of America cited an instance of the faith of the analytical chemist who uses the spectrograph in determining beryllium in a certain material. The maximum sample that can be presented for excitation contains 0.001 microgram of beryllium. The spectrographer promptly throws aTvay most of the radiation and uses only 30 billionths of that emitted. Thus, he is using as his sample 30 billionths of 0.001 microgram or gram. Commenting on instrumental analysis, Mr. Churchill reminded his audience that most modern objective methods and instruments are methods and instruments for doing faster or in greater volume certain tasks which can be done more slowly and in less volume by classical or traditional methods. Illustrating this point he reviewed a case history of one of the company’s plants, where the analysis of aluminum alloys developed from the use of traditional or classical methods to a stage n-herein the work was done spectrochemically-that is, by photographic spectroscopy-and finally is being done by the use of direct-reading spectrographs. The speaker reported the relative productivity of workers in these three stages of evolution has been in the ratio of 4 :20 :60. This is a 15-fold increase in productivity and speed in changing from subjective methods to those of increasing objectivity and with an increase in both precision and accuracy.
“Is it any n+onder,”said 1Ir. Churchill, “that some of us older chemists, who experienced some little difficulty in learning to weigh to tenths of milligrams or even as microchemists to weigh t o micrograms, are a bit appalled by the brash temerity of these modern-day analytical chemists who go so far into infinitesimals? No wonder we must bolster our faith with the intricate formulas of statistical analysis, and little wonder we have an almost idolatrous faith in the laws of probability.” Mr. Churchill’s entertaining and instructive discussion of things analytical closed with two thoughts worth leaving with our readers. First, he criticized in no uncertain terms the poor “housekeeping” in many laboratories. As the dean of analytical chemists in an area where analytical chemists absund, his observation that too many laboratories are untidy must be accepted at its face value. Secondly, his point that recognition of status by the public while devoutly wished for is something to be earned, was sound, sane advice. “That means in the calling of analytical chemistry,” he concluded, “high standards of preparation and performance. It means the maintenance of alertness of mind even after the days of academic preparation and industrial training are over. It means devotion to one’s assigned tasks and their fulfillment. It means an acknowledged dynamic willingness to be a servant t o the useful calling which we name analytical chemistry.’’
Fresenius Celebration
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May issue of the Zeitschrift f u r analytische Chemie will celebrate the one hundredth anniversary of the founding of the world-famous Fresenius Laboratory by the old master of analytical chemistry, Karl Remigius Fresenius. The centennial celebration will include an appropriate historical review article and a large number of papers on specialized subjects written by outstanding analytical chemists located in various parts of the world. In this way the international character of the celebration will be emphasized. The Zeitschrift f u r analytische Chemie has been closely linked with the Fresenius Laboratory and the family of Fresenius. The present director of the laboratory is the grandson of the founder. Much of the laboratory, including the extensive library, was lost during the late mar. Those desiring more specific information concerning the special issue should communicate directly with the editor, D. Kurtenacher, whose address is Verlag von J. F. Bergmann, Munich, Germany. HE
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The first in a series of summaries of crystallographic data on compounds of interest in research and analysis is presented on page 274 of this issue.
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