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Paints and the Part they Play in the Fight Against Corrosion. H. Hollis, B.SC., A.R.I.C., and L. J. COLEMAN (Chemical Inspectorate, Ministry of Supply). Dr. W. F. Higgins (Magnesium Elektron Ltd.) stated that the importance of surface preparation could not be too greatly stressed. Continuing, he said that the authors had made what seemed to him to be an extraordinary statement, although up to a point it was really common sense. They had said that a primer was applied to protect the metal surface, and then the top coat or maybe the intermediate coat was applied to protect the primer. He gathered they were not referring to protection merely against physical damage. But why did they do that? It should not be necessary. On the previous day it was stated by Mr. Rogers that it was done because the ratio of binder to solid was small, and therefore there was not good adhesion. Dr. Higgins suggested that, if a primer were applied to the metal surface and it had not good adhesion, one could not make it good by putting another coat of paint on top of it.

The cathodic protection of ships against corrosion has a long history, for it was first applied in 1824 by Sir Humphry Davy for the protection of the copper sheathed hulls of British warships. Here the author describes the modern art of cathodic protection which can be used at every stage of a ship's life from the fitting‐out period onwards. Besides its main use for the protection of hulls, the method is applicable to propellors, stern gear, cargo compartments, etc., and it can result in very considerable savings in repair costs. The author also discusses the cathodic protection of other marine structures such as floating docks, mooring buoys, etc.

Continuing from last month, the development and choice of materials for giving the best protection are discussed—galvanic anodes, anodes for use with impressed current and graphite anodes. A survey of the applications and limitations of cathodic protection is also included.

The theory of cathodic protection is established on sound scientific principles and its practical effectiveness is now widely recognised. Substantially similar conclusions have been reached by nearly all investigators, although the technique of application may vary very considerably. Here the author discusses in outline cathodic protection in relation to some of the methods of investigation. Next month will continue with the development of specialised equipment which has become available and the practical applications and limitations. Cathodic protection is not yet an exact science, being more of an art which requires considerable experience for its successful prosecution.

Over two years ago the first issue of CORROSION TECHNOLOGY appeared. In the 25 issues that have followed we have published over 90 major signed articles, 250 commentary items, 250 abstracts of corrosion literature and hundreds of other items and features, all dealing directly or indirectly with problems of corrosion. During its comparatively short life, CORROSION TECHNOLOGY has grown up and made many contacts throughout the world. To mark the achievement of our first 24 months' publication we invited some of our friends from the worlds of science and industry to set down a few of their thoughts on corrosion matters for publication in this issue, and we are privileged to be able to print the following contributions.

WATER SERVICE PROBLEM. An unusual solution was found to a perplexing problem in the water treatment of an air‐conditioning system in Lancaster, Pennsylvania, U.S.A. The system, comprising a 150‐ton compressor‐type comfort cooling system and a 510‐ton Carrier absorption refrigeration unit, installed in offices and plant in June 1955 and June 1956, respectively, is serviced by separate cooling towers. Within three weeks of the 510‐ton unit going into operation, serious operating difficulties, which virtually shut down the air‐conditioning equipment, developed. Water Service Laboratories, who are specialists in water problems, were called in to survey the cooling water problem. Samples of make‐up water from each of the two cooling towers located on the roof of the plant were sent to the laboratories for analysis.

SPONSORED industrial research by independent organisations has been a feature of American industry for many years and one need only mention the famous Battelle Memorial Institute, which has just completed its quarter century, as an example. In Britain it was not until 1946 that an institute, which could be described as being at all comparable in conducting research on a non‐profit basis, was founded by the late Colonel W. C. Devereux, C.B.E., at Fulmer, Bucks. It was founded primarily as a service to British industry and since its inception the programme of the Fulmer Research Institute has included the investigation of over 1,100 problems dealing with service failures, the design of equipment and the development of materials and processing. Results arising from sponsored industrial research, including patents, belong solely to the sponsors. The Institute is staffed and equipped to deal mainly with metallurgical problems and this includes the study of corrosion and stress corrosion of metals and alloys exposed to various atmospheres.

PILGRIM'S PROGRESS. ‘A MINISTRY of metal care or preservation is now as necessary as a Ministry of Supply’ was one of the statements made by Mr. T. Henry Turner, chairman of the Corrosion Group, when he delivered the third chairman's address recently. Entitled ‘A Pilgrim's Progress from Corrosion,’ the address contained a fascinating account of Mr. Turner's personal fight against corrosion and the many fields in which he has met its challenges over a period of 35 years. From early work with sprayed metal coatings and nickel plating to the diverse corrosion problems which confront the chief chemist and metallurgist of a railway company, Mr. Turner has encountered at one time or another most aspects of industrial corrosion. It was he who during the last war suggested the use of modern boiler‐water treatment, with inhibitors to prevent boiler corrosion and to avoid descaling, which was subsequently adopted by the Royal Navy and the Merchant Navy. He was the first to have stainless‐steel components made for his bicycle and claims that his 1926 motor car was the first in the country to have its bumpers specially chromium‐plated on a heavy undercoating of nickel. The introduction of mirror‐polished stainless‐steel knives had, according to his records, reduced the number of sharpenings necessary over a period of seven years from about 7,000 to 14.

HEAVY ATTENDANCES AT OUR FIRST CONVENTION. CORROSION TECHNOLOGY's first Convention can fairly be judged to have been an unqualified success. Of the 517 registered delegates, over 450 actually attended at the Central Hall, Westminster, and throughout the two days, when 13 papers were presented and discussed, the Hall seldom contained less than 300. Delegates included a fair sprinkling from overseas and the following countries were represented: Canada, Denmark, France, Germany, Holland, Italy, Norway, Portugal, Sweden, Switzerland, United States and the U.S.S.R.

At the Central Hall, Westminster, on Tuesday and Wednesday, October 15–16, the Corrosion Convention organised by CORROSION TECHNOLOGY will take place. Papers on a wide range of aspects of the corrosion problem will be delivered by authorities from industry and research. Delegates to the Convention will receive pre‐prints of all the papers, but for the benefit of readers who cannot attend we print below abstracts of a selection of the papers which are available as we go to press.