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THE term synthetic rubber is strictly related only to a product which is physically and chemically indistinguishable from natural rubber; no material has been developed fitting such a definition and synthetic substances which possess properties approximating to those of the natural product are generally regarded as synthetic rubbers. More exact definition has been attempted by many authors in particular to so‐regard only those products which are capable of vulcanization, thus turning from plastic to clastic bodies. No new word describing the synthetic bodies has been accepted and it will now prove difficult to divorce the term “synthetic rubber” from any material showing reasonably comparable properties with natural rubber.

During the last year the use of rubber and its derivatives as anti‐corrosive lining agents has been brought into what might be called ‘daily newspaper prominence’ by the completion of two projects using vast quantities of these materials. These projects—the lining of the various parts of the Associated Ethyl Co.'s bromine plant at Amlwch, Isle of Anglesey, and the preparation of the ‘world's largest rubber bag’ for the Mill Hill reservoir at Easington, Co. Durham—are striking examples of the development of this branch of chemical engineering. However, although it is only recently that such large amounts of rubber have been used in single undertakings, this does not minimise the important position which this extremely adaptable material has held for very many years in anti‐corrosive work.

For the purposes of this article, adhesives, lutes and putties are excluded even though many of them have applications in the corrosion‐resistant field. Included are the pouring and mortar‐type cements based on bitumen or sulphur, sodium and potassium silicate solutions, silica sols, rubber or synthetic rubber latices, and synthetic resins. The author considers the composition and working properties of these cements and surveys present trends in their use in industry. Recent and possible future developments are covered.

The purpose of this paper is to investigate the recession effects in market efficiency of natural rubber futures contracts traded in India.

The research draws inferences from Granger causality and Engle–Granger cointegration tests, which are administered separately on 14 year daily price data spanning into two distinct, non-overlapping time series of 2004–2008 and 2009–2017.

Analysis shows that rubber futures market is informationally efficient in price discovery. The results of cointegartion tests indicate that a long-term relationship does exist between futures and spot prices of the natural rubber in India. The recession effects in the market efficiency of rubber futures contracts are evident from the increase in optimal hedge ratios estimated with the cointegration methodology.

The study pursues a simple cointegration methodology to assess the causal relations between spot and futures market prices in the Indian context. Future studies investigating the long-run causal relations, with error correction framework, between spot and future prices of rubber from other leading rubber producing countries can validate the findings more on this issue.

The research expects to pass on vital information inputs on the implications of future contracts to rubber traders for managing their portfolios. The study of this kind definitely will be a great help to farmers and exporters who are potentially interested in gaining access to a hedging vehicle.

The paper is unique in terms of understanding the effects of economic recession in information efficiency of futures market. Moreover, a limited number of studies have explored the functional utilities of rubber futures in emerging market context.

IN consequence of the rapid progress in aircraft development in the past decade it has been necessary for cable manufacturers to provide an ever‐widening variety of cables to meet the special needs of aircraft designers.

The use of natural rubber and synthetic rubber for application to tanks, vessels and pipes, etc., in order to provide an anti‐corrosion lining, has been firmly established and accepted in the chemical engineering and allied industries for very many years. At the present time, such linings are used very extensively and have undoubtedly proved their worth and reliability in spite of the advent of ‘plastics.’

In recent years, considerable advances have been made in the prevention of leakage of liquids and oils past moving surfaces. Leakage is the most common source of complaint with regard to hydraulic machinery, in which field the authors have had considerable experience. The subject covers a wide field and, has been limited by excluding hydraulic joints. For the purpose of these papers, a hydraulic seal is defined as one whose function it is to prevent the leakage of liquid between surfaces having relative movement.

From November 29 to December 2 the Empire Hall at Olympia, London, will be given over to what will probably be the world's largest display of products, processes and services for use in the prevention or limitation of corrosion. Over 120 stands will be shared by 94 exhibitors, each contributing in some way or in many ways to this cause. The extensive preview in the following pages is divided into sections. However, the grouping is general and reflects only one aspect of a company's activities. Therefore a complete examination of items is recommended.

HOW OFTEN does one hear the aggrieved tones of a sufferer asking why he must put up with leakage troubles ? All too frequently such situations occur in all of the very many branches of hydraulics and it seems a pity that in many instances the trouble need not have occurred at all. Obviously, the art of scaling is far from perfect and, in fact, this branch of technology is undergoing some fairly radical development at the present time. Nevertheless, although seals are a necessary evil, many of the occasions when seal trouble is experienced could have been averted if the correct seal had been chosen in the first place and then used to the best advantage.