VOL.3, No. 4
.
L A C Q ~ AES RP~ ROTECTIVE COATINGS
437
cars, tank cars, trolley cars, buses, trucks, and nearly all American makes of automobiles are being lacquered today. Steel frame-work and even exterior sandstone and skylights have been lacquered, a t least experimentally. In the Book-Cadillac Hotel a t Detroit, above the mezzanine floor, all the wood and metal trim is finished in lacquer. A textile mill in New England has been refinished in white lacquer enamel. A considerable percentage, possibly forty per cent of the furniture now made in this country is being finished in lacquer, both clear and pigmented. Many ice-boxes, filing cabinets, and a great variety of miscellaneous objects and novelties are now being lacquered. Lacquer gives a beautiful and a durable finish and its use saves time. We have, in these characteristics, the explanation of its recent growth and future promise.
Soap Found Good G e m Killer. "Hot soap suds and water." the good, old-fashioned remedy for all cleansing purposes, has real germicidal properties, according to experiments carried on a t the Army and Navy General Hospital, Hot Springs. Ark., by Dr. J. E. Walker. I n a forthcoming issue of the Journal o j Infectious Diseercs, Dr. Walker says that any ordinary soap used with a reasonable degree of care will kill several kinds of bacteria. notably those that cause pneumonia, gonorrhea, diphtheria and several of the pusforming organisms. The dysentery and typhoid bacilli die harder. Strong soaps made of what is known as saturated fattv acids are necessanr to annihilate these tough ones. A salt water soap, prepared exclusively from cocoanut oil, is the most readily available efficient soap to rid the hands of possible typhoid bacilli. Unfortunately an all cocoanut oil soap is too irritating to the skin for ordinary use.-Science Service Cadmium Plating - Protects Steel. Cadmium plating is as effective in preserving iron and steel from corrosion as zinc, metallurgists a t the U. S. Bureau of Standards find. Zinc plating or "electrogalvanizing" is especially valuable in commercial processes because i t continues to act as a protection t o the underlying iron or steel even when partially worn away. Thir is the result of an electrochemical reaction between the base metal and the coating. The two in contact with a liquid such as a water solution of any chemical salt act like a wet battery. Automobile parts subject to corrosion. such as rims, nuts, and bolts, are common examples of electrogalvanized iron. Cadmium has been suggested for use in this way but it was not previously known just how i t would react. The experiments carried out in the metallurgical division by H. S. Rawdan have demonstrated that it behaves in much the same way as zinc, with same advantages and some drawbacks. It is less readily attacked by air and moisture and in consequence stays bright longer than zinc. It could suitably replace nickel plating in many places and it would give much more lasting protection t o the iron or steel base. Likewise a coating of cadmium will last longer than a coating of zinc of the same thickness. I t has, however, the serious disadvantage of being expensive to prepare. It is possible that it may he made more cheaply if the demand is ever sufficient to stimulate large quantity production.-Science Senice
