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This paper is concerned with the theoretical and practical engineering development issues, necessary for the design, build and test of an afterburner thrust augmentation system for a model aircraft gas turbine engine.

Research into key combustion parameters including, flame holder diameter, flame holder edge velocity, burner velocity and equivalence ratio were undertaken. This information was used as the basis for the design and fabrication of the afterburner combustion system. The after burner system had been designed to fit a Wren MW54 model gas turbine engine, that included FADEC control for the mother engine. Substantial testing of the afterburner system was undertaken.

Changes in “dry” and “wet” jet efflux temperature while the engine is accelerating from idle to full power are found. The increase in temperature between the dry and wet case are not markedly different, demonstrating the poor quality of the afterburner flame: the testing of the afterburner system resulted in limited flame substantiation being achieved.

Further research is required and is currently being undertaken, into the computational modelling of fuel atomisation issues and further engineering of the fuel injection system.

This afterburner design may eventually be adopted by Wren Turbines for economic production.

Provides further information on the engineering and efficiency problems associated with very small‐scale gas turbine engines.

Most countries seek to impose control on the chemical treatment of both human and animal food. Some, such as the U.S.A., attempt it by highly detailed regulations, in terms most orthodox and almost psychically specific, which seem most complicated compared with our own simplified food ordinances; other countries, such as many of the newer states, treading cautiously in their virgin fields of law‐making, pass broad, enabling laws, leaving details to be filled in later. Although the object is the same in all countries, it is nothing short of amazing how the pattern of legislation manages to be so divergent, and applied for reasons that are not always apparent. In published regulations and laws, there would seem to be less intent on making a country's food exports conform to the legislative requirements of importing countries than in prescribing standards for its home products; the end results have produced food law chaos, rarely seen in other branches of law. A notable exception, the only one, to these irregular developments, and with particular reference to food additive control, are the common decrees and directives of the European Economic Community, representing the six Common Market countries. Its Council prescribes quality standards for individual foods, specific purity standards for preservatives and other additives which may be used for human consumption, and although this standardisation is only beginning, it deserves study, especially the manner in which the community regulations are enforced.

IN the October number of THE BRITISH FOOD JOURNAL, while disclaiming any intention of supporting or opposing any political party or any section of politicians, we stated our opinion that the fiscal policy which has been outlined before the country by Mr. CHAMBERLAIN is eminently one which requires to be put to the test of experiment and which cannot be profitably argued about upon theoretical bases. In connection with the allegation that by following the policy of leaving our doors open to those who shut their own doors in our faces, we are able to obtain goods at less expense than would be the case under other conditions, we pointed out that it would be well for the public to consider whether that which is so cheap may not also, to a great extent, be particularly nasty. The desirability of considering the nature and quality of so‐called “ cheap ” foods, supplied to us by various countriies without restriction, does not, as yet, appear to have entered the heads of those who have made matter for political controversy out of what is, in reality, a scientific question. The facts are not sufficiently known, or, in consequence of the proverbial carelessness of our generation, are not clearly appreciated. And yet, as it seems to us, some of those facts are of paramount importance to those who desire to study the subject in a calm and scientific manner and outside the region of political turmoil. What do we get from the various countries whose producers and merchants are free to “dump” their goods in this country without the restrictive influence of duty payments? Great Britain has made it known to all the world that “Rubbish may be Shot Here,” and we venture to say that the fullest advantage has been taken, and is taken, of the permission. From America, France, Germany, Italy, Holland, and Belgium, in fact from every producing country—including now even Russia and Siberia, we get inferior or scientifically‐adulterated articles which are sold to the public “ cheap.” Milk and butter scientifically adulterated, or produced under improper conditions in such a way that their composition becomes the same as physically‐adulterated products, condensed “milk” minus cream, cheese practically devoid of fat, or “ filled ” (as it is called) with margarine, all reach us in enormous quantities from most of our near and dear neighbours. Butter and certain wines and beers, loaded with injurious ‘ preservative” chemicals and the sale of which is prohibited in the country of production, are sent to the easily‐entered British “dumping‐ground” for the delectation of its confiding inhabitants. “Tinned” foods prepared from raw materials of inferior character or of more than questionable origin, are copiously unloaded on our shores to feed our complaisant population,—instead of being consigned to the refuse destructors which should be their proper destination; while, every now and then, when something worse than usual has been supplied, representative specimens of this delectable class of preparation are proved to have caused outbreaks of violent illness—those so‐called ptomaine poisonings which, of late years, have increased in number and in virulence to so distinctly alarming an extent. Flour made from diseased or damaged grain, or itself “ sick ” or damaged, and so “ processed ” as to mask its real condition; flour, again, adulterated with other and inferior meals, are “ goods ” supplied to us in ample amount for the benefit of those whose mainstay is some form of bread or flour‐food. The list might be continued literally ad nauseam.

Research over the last decade or so has made it clear that quality teachers matter to student achievement. What is less clear is the ways in which they matter and how we can prepare such high-quality teachers. Nowhere is this lack of clarity more evident than in special education, where we have few studies on teacher quality and even fewer studies on the type of preparation opportunities that would lead to high quality. Thus, it is difficult to make evidence-based decisions about how quality special education teachers should be defined and prepared. As a field, we have to turn to research in general education to provide a sense of some of the dimensions of teacher quality and effective teacher education. In this chapter, we provide a summary of the research on characteristics of highly qualified teachers and what we know from the research on teacher education and professional development that might foster these qualities, both in general and in special education. Part of our discussion centers on the concerns surrounding this body of research and the challenges of applying the findings to the field of special education. Although these challenges pose considerable problems, we are optimistic that potential solutions exist and can be reached through an alignment of initial teacher education and induction.

Food and its effect on public health is a subject which takes an important place in Part II of the Ministry of Health's Report for 1951, and the Ministry of Food, in recognising the seriousness of food poisoning, has given prominence to the section devoted to food contamination by including, in one of its October Bulletins, a summary of this part of the Report. Food poisoning is described in the Report as a problem which grows more and more important, and which calls for a much higher standard of hygiene in food handling and its preparation. Figures compiled from the reports of the Public Health Laboratory Service, from bacteriologists in certain hospital laboratories, and from medical officers of health show that the total number of incidents notified in 1951 was 64 per cent higher than the number notified in 1949, but there is evidence that the actual number of persons affected by food poisoning was far in excess of the number of cases reported. Laboratory facilities for the investigation of food poisoning vary considerably in different districts, and medical officers are not always informed in time to carry out a full investigation; it is, therefore, difficult to obtain an accurate picture. In 255 outbreaks (47 per cent of the total) the source of contamination was traced. Of these outbreaks 101 occurred in canteens, 41 in hotels, cafés and restaurants, 9 in butchers' shops, 83 in hospitals, nurseries and institutions, and 18 in other places. The number of outbreaks traced to canteens is disturbingly high, but it should be remembered that canteen outbreaks are investigated and reported more frequently than outbreaks originating in shops and restaurants. When infected persons disperse from restaurants to their homes before the onset of symptoms, tracing the source is always difficult and often impossible. There is no reason to suppose that food poisoning arises less often in restaurants than in canteens. The figures reflect the difficulties of discovering and investigating outbreaks where the patients live in a number of different areas; they do not indicate the relative incidence of poisoning in canteens and restaurants. The Report states that 48 per cent of all outbreaks in which the food responsible was identified were traced to processed and made‐up meat such as re‐heated meat, stews, sausages, brawn, rissoles, gravy and stock. Out of 435 outbreaks in which the food thought most likely to have been responsible was traced, other foods—in addition to the meat dishes mentioned above—contributing to this type of infection were trifles, ice‐cream, custards and cream buns, also ducks' eggs. Milk was mentioned in 16 outbreaks. Inadequate standards of personal hygiene and faulty methods in preparing food for large numbers were the main reasons for contamination. Harmful bacteria usually get into food from insufficiently cleansed hands. Every effort must, therefore, be made by employers to provide kitchens and water‐closets with hand‐basins, abundant hot water, soap, nail brushes and clean towels. Though education in the hygiene of food preparation is now spreading, it still lags far behind what is necessary. Members of the public can speed the progress by actively insisting that their food is prepared and served with due regard to cleanliness at all stages. Reverting to the fact that nearly half of the outbreaks traced to specific foods were associated with processed, made‐up, and re‐heated meat dishes, the Report states that, if all meat dishes were cooked shortly before they were to be consumed, and if they were eaten while they were still hot, there is no doubt that the incidence of food poisoning would show an immediate and substantial decline. If food has to be prepared in stages, then precautions should be taken to prevent the growth of bacteria. After cooking and rapid cooling, it should be refrigerated until it is wanted, If it is to be re‐heated, this should be done rapidly and the food brought to boiling point. The Report refers to the setting‐up, by the Ministries of Health and Food, during the year under review, of two Working Parties and a Committee; these bodies have been making enquiries and have produced reports on the precautions to be observed in various branches of the food industry. These reports, have already been referred to in previous articles. Although there is no doubt that great improvements have been made in the handling of food—due to the enthusiasm of Medical Officers of Health and Sanitary Inspectors—it is generally realised that a persistent drive, requiring a long sustained effort and embracing complete health education of the food trade and the consuming public, is needed before safe food becomes a reality. Public opinion has been given the necessary impetus, and, on the business side, it is now obvious that good sanitary practices are also good trade practices, and that there is no conflict between the two interests. The way in which premises, the design and condition of equipment, and the human element affect the practices which are enforced or permitted in any particular food business, has a part to play in achieving and maintaining a high standard of food hygiene. Many food handlers have a confused idea of the difference between detergent and sterilizing action, and of the fundamental principle that sterilization must follow, and not precede nor be substituted for, cleaning with a detergent. On the other hand, it is very encouraging to visit so many small catering businesses, such as transport and other workmen's cafés, where the owner is intensely proud to show off the improvements and the efforts he has made to raise his food handling to a higher standard. At the other end of the scale, some multiple caterers have utilised their highly organised resources continuously to improve their premises, equipment and methods. There is, we all agree, endless scope for further health education.

Aarhus Kommunes Biblioteker (Teknisk Bibliotek), Ingerslevs Plads 7, Aarhus, Denmark. Representative: V. NEDERGAARD PEDERSEN (Librarian).

This paper focuses on public interest immunity (PII) and disclosure of unused material in the context of criminal proceedings. PII used to be referred to as Crown privilege and was hardly ever raised in connection with criminal proceedings until 20 years ago. Nowadays, PII issues are often raised in connection with criminal proceedings, particularly during the process of disclosure of unused material for the purposes of criminal trials.

Most of this Board's senior staff have now been appointed. Mr Alan Swinden became Director in July, Mr Frank Metcalfe is the Chief Education and Training Officer and Mr Mostyn Morris becomes the Board's Financial Controller in November.

Even those most skilled in the art of diagnosis occasionally need to be reminded that common things occur most commonly; it saves them chasing obscure signs to uncommon conclusions. Having spent several uncomfortable days in snuffling and snivelling, sneezing, streaming; sequestered with the piles of wet handkerchiefs mounting, with which we believe we have developed entirely novel and hitherto untried methods of nose‐drying; in all this, we felt the urge to write a little to those who search for uncommon things in food about that commonest of all common things—the common cold! This may not be so important after all, as there has at last been developed satisfactory culture‐techniques for the common cold viruses and cold vaccines are now distinctly probable, so that for generations unborn, the common cold may become an uncommon infection. Who knows?