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The advantages of reclaiming as much condensate as possible in any steam‐generating system are manifest. The return of hot water to the boiler results in a considerable reduction in fuel and water consumption. In addition, a low make‐up will give rise to a lower rate of corrosion attack due to carbon dioxide generated from dissolved bicarbonates. However, such a procedure greatly increases the length of piping and number of fittings which are exposed to attack. The corrosion of steam and condensate return lines, and also of steam‐using equipment, can become a major problem. Perforation of steam jackets, steam coils, pipes and fittings; choking of steam traps with corrosion products; leaking valves and joints are serious enough in themselves. The cost of replacing the corroded equipment is often considerable and excessive damage may be caused by the ingress of steam or water to the product being manufactured. In addition, a very high labour cost is often involved. Repairs to damaged plant must usually take place at weekends and during holiday time, when overtime rates are paid.

Inhibition of corrosion is a specialised division of the science of water treatment. The necessity for treatment of industrial waters for the prevention of scale deposits and to adjust the dissolved constituents to suit a particular manufacturing process is clearly recognised, but the conditioning of the pretreated water to prevent corrosion is often not considered at all or at least given only superficial attention. It is usually not until the incidence of corrosion poses maintenance problems and affects the manufacturing process that the corrosion aspect of water treatment is looked at seriously.

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.

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.

The treatment of water for use in steam‐raising plants has two primary objects: firstly, to maintain efficiency of operation by preventing the formation of scales and deposits on heating and cooling surfaces and in water‐carrying pipelines and, secondly, to prolong the life of the equipment by preventing corrosion of metal surfaces with which the water comes into contact. Corrosion is perhaps less obvious because the effects are not always evident until it is too late and replacement of corroded sections becomes necessary. Troubles caused by the accumulation of corrosion products, and damage by corrosion, can be avoided if appropriate agents are employed to treat the water circulating in the system. This article describes the properties and use of cyclohexylamine, a material which has found widespread application for the treatment of boiler water to prevent corrosion of metal surfaces by dissolved carbon dioxide.

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.

Printed below is a selection of some of the many questions raised on the first day of the Corrosion Convention organized by CORROSION TECHNOLOGY at the Central Hall, Westminster, on October 15–16. Unfortunately, space does not permit full justice to be done to this important aspect of the Convention, so great were the number of questions and discussions instigated by the 13 papers which were read, covering a wide field of corrosion problems. A selection of questions arisng from the second day's papers will be published next month.