The Shoemaker's Son May Go Barefoot

But when α motor manufacturer has electrical equipment that fails frequently because of high operating temperatures, he uses DC Silicone Insulation. Take an absorption type dynamometer, for example.

PHOTO COURTESY HOWELL ELECTRIC MOTOR COMPANY

Using a 75 h.p. frame and stator, Howell engineers designed and built this absorption type dynamometer to determine torque in electric motors. They chose this type of dyna­mometer because motors are easily hooked up and readings are quickly made. The idea was good but Class 'B* insulation wasn't good enough.

Average life of the windings was limited to 2 to 3 months and only motors of 75 h.p. or less could be tested without burning out the windings. To this practical problem the Howell engineers found the practical answer. After several failures they rewound the dynamometer with our Silicone (Class Ή') Insulation.

Results were even better than they iioped. The silicone insulated dynamometer has been in service now for 18 months—over 6 times the average life of Class 'B' windings—and the insulation is still in excellent condition. Further­more, the dynamometer is being used to test motors ranging up to 150 h.p.—twice the previous capacity.

That's just another one of the many field reports that confirm the findings of our Motor Test Laboratory—DC Silicone Insulation has at least 10 times the life and 10 times the wet insulation resistance of Class 'B' under similar operating conditions. If you want more evidence of the superiority of Silicone Insulation write for leaflet G 4-T.

DOW CORNING CORPORATION M I D L A N D , M I C H I G A N

Atlanta · Chicago · Cleveland · Dallas New York · Los Angeles

In Canada: Fiberglas Canada, Ltd., Toronto In England: Albright and Wilson, Ltd., London

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Berzelius Centenary The hundredth anniversary of the

death of Jons Jakob Berzelius passed recently, reminding us tha t it has been only a century since one man was able to command all of the chemical knowl­edge t ha t had been developed a t his t ime. A t least, it is said of Berzelius tha t he was the last of the old masters who achieved this omniscient state within the world of chemistry.

Berzelius' history a s a student should offer consolation to those who are finding that Chem. Τ is a tough sub­ject. H e did poorly in his studies, and on finishing his work in the gymnasium t he authorities granted him a certificate stating t ha t he justified only doubtful hopes. I n his study of medicine which followed he was passed in chemistry only through the optimism of his pro­fessor. However, soon after leaving college he began his chemical work which at t racted much attention and brought him the highest honors. One of his earliest achievements was the de­termination of the combining weights of elements. Within a little more than 10 years, it is reported, he completed this for 43 of the elements by prepara­tion and analysis of their compounds. I n doing so he developed many quanti­tat ive analytical methods, after which analytical chemistry was given recog­nition a s a s tandard which could no t be ignored in judging a chemical theory.

Berzelius was the inventor of the modern alphabetical chemical symbols. H e was also the originator of an im­por tant Jahresbericht a n d the writer of a great textbook which passed through five editions and was translated into several languages. Par t ly through these media, his ideas were spread so widely and the brilliance of his scien­tific thought was so clearly shown that he became recognized as t he leading thinker in tha t science a t the t ime and was a virtual maker of laws whose opinion carried more weight than the experimental data of many men.

To enumerate his achievements would require pages. Here we can only pay tr ibute to the memory of one of the greatest figures in the advancement of t h e science of chemistry.

Mloman Pottery As products of the ancients are in­

vestigated and analyzed, we are re­peatedly amazed at the extent of their technology. Oftentimes the physicians or artisans of those earlier civilizations used substances or techniques t h a t aro in common use today. While we hesi­

ta te to give them credit for under­standing fully the use of such things, we must admire their ingenuity in hav­ing discovered so many different ma­terials and applying them to uses which to this day may not have been mark­edly improved or only recently redis­covered.

One such case is the use of lead glazes on Roman pottery in Asia Minor, as reported recently in the American Journal of Archaeology by Ear le R. Caley of Ohio State University, wdio thus traces modern ceramic processes back to Roman formulas. Lead glaz­ing is widely used today on many mod­ern ceramic products, including most dinnerware, bu t according to Caley, factual information as to wrhen this process was introduced had been lack­ing.

I n the work reported by Dr . Caley, two glazes from fragments of Roman pottery from excavations in Tarsus in southern Turkey were analyzed by semimicrochemical techniques. Both were found to contain a considerably higher proportion of lead than modern glazes, and this difference is offered as a means of detecting modern forgeries of ancient pottery.

Cleanliness T h e scrupulous cleanliness of the

Du tch and the Danes has long been legend. An executive in a large food machinery manufacturing concern re­cently told one of our editors of a situ­at ion which exists in the food process­ing industries which points up this dis­tinction a t the expense of the American workingman. The Netherlands and Denmark are historic producers of dai ry products and in recent years have been at the forefront of technological developments in this field. There processing equipment is made of stain­less steel, as is its American counter­pa r t , but unlike the American product it is made with lap joints, square corners, and recesses which are not visible upon routine inspection. The inbred conscientious cleanliness of the operators in these countries, however, ensures tha t the vessels will be scru­pulously scrubbed between operations and will remain free of bacteria indefi­nitely. For American installations, wi th their production-conscious crews working under the shadow of the omni­present timeclock, all corners must be rounded, all joints but ted and polished, all parts of the interior readily visible upon cursory inspection. We view wdth alarm, etc., etc., e tc

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