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The purpose of this paper is to explore the scope of robust dispersion control charts in a distribution-free environment, which is a specific case of non-normal control charts. These control charts are skewness-based structures designed to monitor skewed-type processes whilst equally performing under symmetric processes. Moreover, the choice of a suitable control chart for a particular non-normal situation is also suggested.

The probability control limits approach is considered as an alternative way to determine the skewness-based structure of dispersion control charts. The proposals of five robust and two conventional Shewhart-type dispersion control charts are suggested as efficient competitors of skewness correction (SC) dispersion control charts. The evaluation of robust proposals and competing dispersion control charts is done through false alarm rate (FAR) and probability to signal (PTS) measures.

The proposed dispersion control charts are found robust and efficient alternatives of SC dispersion control charts in both normal and non-normal distributions. The FARs and PTS properties of proposed control charts are impressive in all studied cases, and a real-data example also verifies the dominance of proposed control charts.

Conventional dispersion control charts quickly lose their efficiency as underlying process distribution deviates from normality; however, robust control charts emerge as most suitable candidates in such situations. This paper proposes the idea of robust dispersion control charts under a distribution-free structure for the skewed-type process, which is not yet explored.

It must be difficult for many to contemplate the numerous changes in progress and projected without wondering why it all has to happen now. Of course, there have always been with us those who would change everything, even those who would spoil; all seemingly unable to leave anything alone; unwillingly to let us be for what we are. Then there are those who dislike change of any kind in their familiar environment and strangely, children are the most conservative of us all, and others who do not object to change when it is necessary, but only when it is change merely for the sake of change. The changeover to the metric system, or to use one of the grating terms of the new technological language, metrication, must be accepted as a natural sequence to decimal currency and advances in industry. A revolution in weights and measures, it will indeed present very great problems throughout the country and at all levels, which will dwarf those presented by the switch to decimal coinage, for at worst, these may be just confusing to the general public and a price‐raiser in small‐value commodities, despite assurances to the contrary.

This new measure of consumer law of some forty‐odd sections, a short Act by present standards but as far‐reaching as any legislation since the war, establishes a code of conduct in commerce and trade which few will be able to ignore, from the manufacturer down to the counter‐hand. Operative from November 30th of this year, traders will require to urgently consider their sales practices, advertising, labelling and their trade descriptions; sales staff will need to be instructed in their new responsibilities. The new law is not just for consumer‐retailer transactions, but extends to trade between different branches of all trades, so that a retailer will be protected against misleading descriptions and misrepresentations by a manufacturer and the latter against misdescriptions of ingredients or components.

Long before calories and joules were used to indicate energy values in relation to food, popular belief had it that some foods could increase man's output of labour, his physical strength and endurance, even his fertility. The nature of the foods varied over the years. From earliest times, flesh foods have inspired men to “gird their loins” and “put on armour”, but too long at the feasting tables produced sloth of body and spirit. Hunger sharpens the wit, which makes one wonder if that oft‐quoted statement of poverty and hunger before the Great War—“children too hungry learn”—was quite true; it is now so long ago for most of us to remember. Thetruism “An army marches on its stomach” related to food in general and relating feats of strength to individual foods is something more difficult to prove. The brawny Scot owes little to his porridge; the toiling Irish labourer moves mountains of earth, not from the beef steaks he claims to consume, but for the size of the pay‐packet at the end of the week!

We can think of those with a cynical turn of mind who might consider not a little of the present output of the parliamentary machine as “harem scarem” law, but the indecent haste, the freak urgency of some politically inspired laws apart, it is only too obvious that law is being made under rush conditions, and the reasons are not far to seek. A hectic, over‐active party executive, feverishly pushing ahead with its policies produces impossible working conditions for the parliamentary draftsmen. Law, whether it is statute or regulation, has never been more complex than it is today; time allowed for parliamentary debate is completely inadequate; too many and varied interests have to be taken into account, to say nothing of the vast range of delegated legislation. The urgency of some legislation is doubtful; it is difficult to see the need for all the hurry; a little more time in proper debate would prevent some of the loopholes which subsequently appear and render the law more comprehensible; incomprehensibility and justice are rarely compatible. As Diplock L J., said in the Court of Appeal in Rex. v. Industrial Injuries Commissioner ex parte Cable (1968) 1 A.E.R., 9, a few months ago—“Judges have been at their wits' end to know what some of the provisions mean. It would be a good thing if time could be found to remedy the blemishes.”

The term “braced frame” is here understood to mean one which has at least enough members to ensure stability, i.e. it must either be “just‐stiff” or “redundant”. The analysis of such a frame on the assumption that the joints are frictionless, so that each member is free to turn at both ends, enables one to calculate primary stresses. In practical frames the connexions at the joints are more or less rigid; bending moments are therefore induced in the members when the joints are displaced. The resulting bending stresses may be of the same order as the primary direct stresses. In addition, the direct stress in any member is itself slightly modified by the shear forces in the other members connected with it, though this effect is usually small.

We give more space than usual to the Conference of the Library Association, but, even so, our correspondent has attempted impressions rather than factual accounts of the papers read. Good as those papers were, the main effect of our conferences is to provide for every type of librarian a sense of community and of unity with librarianship in general. This was achieved in a large measure at Edinburgh. Moreover, as our correspondent suggests, there was interest in problems that do not affect, at least at present, many who participated. Nearly every session, general or special, was so well attended, that we can infer that the vitality of interest in library matters is as great as it ever has been; indeed, it is possibly greater.

At a meeting of the Nutrition Panel of the Food Group of the Society of Chemical Industry, Dr. Joseph Needham, of the Biochemical Laboratory, University of Cambridge, speaking on “ The Biological Nature of the Egg,” pointed out what complex structures were the eggs of birds and other vertebrates. In fact the embryo, which is eventually to develop into the new animal, only occupies a very small space within the total egg. The remainder serves, in one way or another, to keep the organism alive until it is hatched. It is interesting to note that this is not the case in lower animals. The octopus in its egg is not supplied by its mother with enough copper but must obtain more for itself from the surrounding sea. Newts and frogs in their eggs also must to some extent look after themselves. Birds' eggs, however, represent a type of perfectly “closed box” structure which requires many ingenious devices in order to survive. One of these, through which the bird saves itself from being poisoned by its own by‐products, is the fact that the developing embryo does not excrete nitrogen as urea but in the form of uric acid which is more easily deposited as crystals.—Dr. Ethel M. Cruickshank, of the Department of Agriculture, Cambridge, who spoke on the “ Chemical Composition of the Egg,” pointed out that the hen was a physiological machine for turning raw materials into human foodstuffs. The amount of such human food which the hen could produce in a day depended on a number of factors, but to a large extent it was true to say that the bigger the hen the larger the egg. The number of eggs which a hen would lay in a year was a different matter, but an interesting point was the fact that high production had little or no detrimental effect on the quality of the eggs. In considering the composition of the egg one must divide it into three parts. The shell was principally made up of calcium carbonate, although small amounts of magnesium, phosphorus and organic matter were present. The white was composed of four different kinds of protein and could be divided into layers of thick and thin white. The proportion of thick to thin white influenced the culinary value of the egg. Together, the four proteins in the white contained the essential amino acids which made “ first class ” protein. Egg white contained minerals and also supplied valuable amounts of vitamin B. The yolk contained two proteins which were also shown to be of “ first class ” quality. Besides protein the yolk contained 30 to 32 per cent. of fat. Numerous minerals were present, including relatively rich amounts of easily assimilable iron. Vitamins A, D, B1 and B2 were also present. The anti‐rachitic vitamin D was of great significance in the diet. Dr. Cruickshank also discussed the factors in the diet of the hen which might give the yolk an unpleasant taste or a strange colour. Although the amount of fat, and hence the total food value of the egg, could only be influenced to a slight extent by the diet of the hen, the nature and flavour of the egg could be very strikingly altered by feeding mashes containing, for example, hemp seed or linseed oil. As regards vitamins, it was essential that plenty of these should be present in the diet of the hen in order that her egg might be of high nutritive value. As regards minerals, it was very well known that by feeding a hen a diet which was short of calcium a thin shell was obtained. However, the calcium content of the yolk and white were not affected. The amount of iodine in eggs was affected by the amount in the hens' food, although iron and copper appeared to be independent of the amount present in the diet.—Dr. S. K. Kon, of the National Institute for Research in Dairying, Reading, spoke on the nutritive importance of eggs in the diet. He stressed that eggs share with milk the ability to cover nutritive requirements during the period of rapid development. The vitamins, minerals and “ first class ” protein in eggs made them one of the protective foods. In particular, eggs supplemented very well the proteins present in cereals. Dr. Kon showed in detail how eggs contribute to the various factors of a good diet.—Dr. R. B. Haines, of the Low Temperature Research Station, Cambridge, spoke on the preservation of eggs. He showed how hens' eggs were in a state of rapid change. The aim of storage was to retard or stop this change and prevent the attack of outside agencies such as micro‐organisms. Although storage only affected the nutritive value of eggs to a very minor degree, any loss of palatability and cooking quality was a clear indication that certain slight chemical changes had taken place. Dr. Haines mentioned three methods for the large‐scale storage of eggs. The first was cold storage, the second, storage with the partial addition of CO2, and the third, full gas storage. For other purposes, drying or freezing could be used. Problems connected with the storage of eggs led to the consideration of questions of production and handling. For example, “ thick white ” was apparently due to the individual hen. Again, spoilage of eggs by the invasion of bacteria was influenced by the structure of the egg‐shell, which might vary greatly in successive eggs from the same hen or by the “ washing ” treatment which the eggs received. Among many other topics upon which Dr. Haines touched were “ swollen ” and “ flabby ” yolks due to loss of moisture, “ watery whites,” “ sunken ” and “ sided ” yolks due to chemical changes, and eggs with “ whiskers,” due to the growth of fungus on the shell.—Miss Mary Andross, of the West of Scotland College of Domestic Science, Glasgow, gave the final paper on the subject of “ The Cooking of Eggs.” Research in domestic science concerned itself with what effect such factors as temperature, time, rate of cooking, acidity, or the addition of salts, might have on the nutritive properties of eggs which were boiled, poached, fried, scrambled or made into omelets, custards, mayonaise, meringues, angel cakes, or sponge cakes. Another important factor which was the subject of scientific investigation was the effect of the age of the egg in relation to its cooking qualities. Miss Andross also discussed the waste of food value which might take place in different methods of cooking, and she concluded by discussing the effects which different treatments might have on the digestibility of the food.