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Publication date: 1 January 1981

Fred W. Kear

Among the many types of printed circuit board etchant now available, there are a variety of notable advantages and disadvantages. This is confusing to the PCB manufacturer because…

65

Abstract

Among the many types of printed circuit board etchant now available, there are a variety of notable advantages and disadvantages. This is confusing to the PCB manufacturer because all of these etchants work relatively well. In order to assess the advantages of a given etchant properly, the circuit engineer must consider all aspects of its use including its effect on plant effluents and the difficulty of recovering etched copper from solution. Peroxide/sulphuric etchant offers distinct advantages in these areas of peripheral cost, as discussed in detail in this paper.

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Circuit World, vol. 7 no. 2
Type: Research Article
ISSN: 0305-6120

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Publication date: 1 March 1975

An intensive 2½ day short course on Printed Circuit Design will be held at the Sheraton Hotel, Copenhagen, on September 3–5th and repeated at the Lendi Hotel, Brussels on October…

27

Abstract

An intensive 2½ day short course on Printed Circuit Design will be held at the Sheraton Hotel, Copenhagen, on September 3–5th and repeated at the Lendi Hotel, Brussels on October 1–3rd, Holiday Inn, Birmingham on October 29–31st and the Holiday Inn, Rome on November 26–28th.

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Circuit World, vol. 1 no. 4
Type: Research Article
ISSN: 0305-6120

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Publication date: 1 September 1899

In a previous article we have called attention to the danger of eating tinned and bottled vegetables which have been coloured by the addition of salts of copper and we have urged…

78

Abstract

In a previous article we have called attention to the danger of eating tinned and bottled vegetables which have been coloured by the addition of salts of copper and we have urged upon the public that no such preparations should be purchased without an adequate guarantee that they are free from copper compounds. Copper poisoning, however, is not the only danger to which consumers of preserved foods are liable. Judging from the reports of cases of irritant poisoning which appear with somewhat alarming frequency in the daily press, and from the information which we have been at pains to obtain, there can be no question that the occurrence of a large number of these cases is to be attributed to the ingestion of tinned foods which has been improperly prepared or kept. It is not to be supposed that the numerous cases of illness which have been ascribed to the use of tinned foods were all cases of metallic poisoning brought about by the action of the contents of the tins upon the metal and solder of the latter. The evidence available does not show that a majority of the cases could be put down to this cause alone; but it must be admitted that the evidence is in most instances of an unsatisfactory and inconclusive character. It has become a somewhat too common custom to put forward the view that so‐called “ptomaine” poisoning is the cause of the mischief; and this upon very insufficient evidence. While there is no doubt that the presence in tinned goods of some poisonous products of decomposition or organic change very frequently gives rise to dangerous illness, so little is known of the chemical nature and of the physiological effects of “ptomaines” that to obtain conclusive evidence is in all cases most difficult, and in many, if not in most, quite impossible. A study of the subject leads to the conclusion that both ptomaine poisoning and metallic poisoning—also of an obscure kind—have, either separately or in conjunction, produced the effects from time to time reported. In view of the many outbreaks of illness, and especially, of course, of the deaths which have been attributed to the eating of bad tinned foods it is of the utmost importance that some more stringent control than that which can be said to exist at present should be exercised over the preparation and sale of tinned goods. In Holland some two or three years ago, in consequence partly of the fact that, after eating tinned food, about seventy soldiers were attacked by severe illness at the Dutch manœuvres, the attention of the Government was drawn to the matter by Drs. VAN HAMEL ROOS and HARMENS, who advocated the use of enamel for coating tins. It appears that an enamel of special manufacture is now extensively used in Holland by the manfacturers of the better qualities of tinned food, and that the use of such enamelled tins is insisted upon for naval and military stores. This is a course which might with great advantage be followed in this country. While absolute safety may not be attainable, adequate steps should be taken to prevent the use of damaged, inferior or improper materials, to enforce cleanliness, and to ensure the adoption of some better system of canning.

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British Food Journal, vol. 1 no. 9
Type: Research Article
ISSN: 0007-070X

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Publication date: 1 January 1944

It is an amazing fact that this country is one of the few that have not adopted a comprehensive system of food standards, but has relied on the administration of general…

58

Abstract

It is an amazing fact that this country is one of the few that have not adopted a comprehensive system of food standards, but has relied on the administration of general provisions as to the purity of food; and it has been evident to officers engaged in enforcing these provisions that they were inadequate to deal effectively with all the cases in which foodstuffs of inferior quality were offered for sale to the public. Local authorities and courts of law have probably done their best within the limits of their legislative power to prevent as far as possible the sale of such foodstuffs, particularly where public health was endangered or there has been gross adulteration, but the subtlety of food adulteration in recent years has given rise to so much controversy as to how far the existing legislation has been contravened that the Minister of Health should be asked at the earliest opportunity to exercise the powers given to him in Section 8 of the Food and Drugs Act, 1938, to draft regulations as to the importation, preparation, storage, sale, delivery, etc., of food, and to include in such regulations a comprehensive system of food standards. There is ample evidence available for the consideration of any committee which might be appointed to draft the regulations. In 1901 a Departmental Committee of the Local Government Board, which had for two years been inquiring into the use of preservatives and colouring matter in food, recommended inter alia the prohibition of formaldehyde or copper salts in food, the limitation of boric acid to 0·25 per cent. in food, and the amount of salicylic acid not to exceed one grain per pound in solid food and one grain per pint in liquid food. There is also the Final Report of the Departmental Committee, 1924, which led to the introduction of the Public Health (Preservatives, etc., in Food) Regulations, 1925–27, which contained provisions limiting the use of preservatives to certain articles of food, prescribing the preservatives which could be used (sulphur dioxide and benzoic acid in specified amounts) and prohibiting the use of a number of metallic, vegetable and coal‐tar colouring matters. More recent still is the Report of the Departmental Committee appointed in 1933 to consider whether it was desirable that the law relating to the composition and description of articles of food should be altered so as to enable definitions or standards to be prescribed, or declarations of composition to be required for articles of food other than liquid milk, and if so to recommend what alterations of the law were required. As a food officer I was impressed on reading this report at the very wide field covered by the Committee in its search for evidence on the many aspects of the problem, and commend its perusal to all who are interested in the subject of food standards. Professional associations, traders' associations, associations of local authorities, scientists, doctors, public analysts, sanitary inspectors and trade representatives submitted their respective views. The report extends over several pages, but, briefly, the Committee were of opinion that it was not practicable to extend standards of definitions to all articles of food, that housewives would not benefit by a multitude of standards, definitions or declarations of composition, as in a large number of cases they were getting articles of the nature, substance and quality demanded, and that no standards or definitions should be laid down and no declaration of composition required without giving the manufacturers or other persons concerned the fullest opportunity of hearing the proposals and submitting their observations. The Committee also recommended that the contamination of articles of food by arsenic, lead, tin, or other impurities which may be contaminated in the process of collection or preparation should be treated as a special question. A further recommendation that specific claims made in advertisements should be deemed to be part of the package label has since been provided for in the Food and Drugs Act, 1938 (Section 6). In their evidence before the Departmental Committee in 1933, the Society of Public Analysts advocated the institution of a comprehensive system of standards and definitions, which would ultimately embrace all articles of food, and as this goes much further than the recommendation of the Committee, the views of public analysts on any new draft regulations will no doubt be awaited with considerable interest. In any case, their observations should be of considerable value when food standards are under consideration. Many suggestions for standards have emanated from commercial interests, and the Chief Medical Officer to the Ministry of Health, in his report for 1938, referring to these suggestions, stated “there is often discernible a desire to stifle competition, and that frequently the grade or qualities to which objection is taken are sound, wholesome articles of food, the suppression of which would be a distinct loss to the poorer class of consumers. New standards should therefore apply to all grades and not only to the higher‐grade articles. In fact, if any preference is to be shown it should be in respect of the cheaper grades. Where there is doubt of the efficiency of applying a standard, the desire should rest not on whether it will create difficulties in manufacture, although, of course, this aspect must be considered, but whether it is in the public interest that a standard should be laid down.” The Chief Medical Officer is to be commended for this timely warning, and it should be borne in mind by those drafting new regulations. It should be ensured that public welfare and not commercial interests should receive first consideration in a matter of this kind. There are many articles of food to which standards of composition are already applicable, including butter, margarine, condensed milk, dried milk, whisky, spirits, etc. There are also presumptive standards for milk and skimmed milk, and semi‐official standards for jam, vinegar and shredded suet. I am aware that under emergency powers the Ministry of Food have introduced standards for numerous articles of food, but these have been primarily introduced in connection with food rationing and other difficulties in connection with war‐time control of the principal foodstuffs. They are no doubt related to the availability of supplies of the various constituents, and therefore subject to alteration from lime to time, as instanced by the reduction in the percentage of meat to be contained in sausages. Except, therefore, as an experiment, these standards cannot be regarded as a satisfactory system, and will probably be revoked immediately the national situation justifies such a course being taken. We should not, therefore, be unduly influenced by these war‐time standards. Despite the desire of public analysis and food officers to have legal standards for all articles of food, it may be found impracticable to fix standards of composition for such articles as meat, fish, fruit, vegetables, eggs, etc., as they are prepared with the minimum of handling and are less likely to be adulterated. There are, however, many articles of food for which at present there are no legal standards as to their nature, substance or quality, and to which such standards might easily be made applicable, such as meat‐paste or fish‐paste, for which you have no guarantee of the percentage of meat or fish present. Just before the war there was a popular demand for cheese‐spreads, some of which contained up to 35 per cent. fat, but in the absence of legal standards varieties of cheese‐spreads may contain much less fat. There is no legal standard for cheese, with the result that whether it is made from skim milk or new milk it may still be sold as cheese. Mixtures of cocoa with starch and sugar may be sold as cocoa, if the fact that they are mixtures (without disclosing the percentage of cocoa) is disclosed on the label. In America milk chocolate must contain a minimum of 12 per cent. milk solids, but there is no such standard in this country. Although there is a bacteriological standard for ice‐cream in the Isle of Man, to the effect that when examined within twenty‐four hours of sale it shall not contain more than one hundred thousand bacteria per cubic centimetre, and no Baccilus coli in one‐tenth of a cubic centimetre, there is no such standard in this country. It has been suggested that ice‐cream should be made from milk, cream and sugar, with or without eggs, and contain a minimum of 8 per cent. of milk fat. An article sold as honey should be solely the product of the honey bee and not a chemically prepared substance. The latter might be designated as “artificial honey,” and labelled accordingly. Fruit juices should be what the name implies, and be manufactured and sold in compliance with statutory requirements. There should be standards for cordials, squashes, jams and preserves. Meat extracts should be made from good muscle fibre and its total creatine content slated on the label. If low‐grade meat is used, including offal, the fact should be disclosed on the label. With regard to statutory declarations on labels, the printing should be of such size that it is easily legible. It should neither be impossible nor impracticable to introduce legal standards for custard powders, baking powders, blancmange powders, pudding mixtures, cake mixtures, and many other foodstuffs which are ordinarily consumed by the public, not forgetting sweets and confectionery, wines and cocktails, milk shakes, and soft drinks. The ramp which went on during 1940–42 in connection with the sale of “food substitutes” was a striking example of the need for statutory standards of composition. It is often contended that if housewives only purchased goods prepared by reputable firms they would receive satisfaction, and while to a large extent this may be true, the fact remains that inferior articles still find their way into shops. There is, of course, the possibility that shopkeepers may be tempted by the offer of a larger margin of profit on goods supplied by firms of less repute. Some shopkeepers even fail to obtain a warranty that the goods supplied to them conform to the requirements of the Food and Drugs Act and Regulations. It is not sufficient for the Departmental Committee to state “that in a large number of cases housewives get articles of the nature, substance and quality demanded,” and leave it at that. An effort should be made to apply standards to every article of food to which the application of such standards is possible. Housewives should no longer be tempted or misled by catch advertisements, attractive labels or wrappings, or the inducement of free gifts. To give some idea of the need for a wider application of standards, a few cases dealt with during the past three years, some of which came under my own personal investigation, are set out below, with the Public Analyst's comments: 1.—Egg substitute.—Contained no true substitute for eggs; consisted of a solution of synthetic gum, probably made by treating cotton with some chemical; containing only 3·8 per cent. solid matter, the rest being water; had no food value.

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British Food Journal, vol. 46 no. 1
Type: Research Article
ISSN: 0007-070X

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Publication date: 1 November 1916

The Professors of the Imperial College of Science and Technology have addressed to Lord Crewe, the Chairman of the Governors of the College, a memorial urging the necessity of the…

13

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The Professors of the Imperial College of Science and Technology have addressed to Lord Crewe, the Chairman of the Governors of the College, a memorial urging the necessity of the encouragement of science and of research. In commenting upon this document the Journal of Chemical Technology observes that “a satisfactory feature of the memorial is the recognition on the part of the signatories that scientific education should be on broad lines.” “We have always contended that an indispensable preliminary to a professional career should be a thoroughly sound general education. Whether or not the study of science is the best kind of study may be a debatable point, but it is certain that exclusive attention to science is thoroughly bad. A man's mind is narrow when he is unable to recognise the importance of things outside his own particular sphere of action, and it is precisely this state of mind that the exclusive study of science tends to produce. It is, therefore, the more necessary, in seeking to secure greater attention to scientific studies in the reform of our educational system, to take care that nothing be done which may curtail the period required for the acquisition of general knowledge. It is far better to delay than to hasten specialisation. A step in the right direction has been made when scientific men themselves state that they do not believe that “an education which includes good teaching of science need be a narrow education,” but we wish that this opinion had been positively rather than negatively expressed. The memorial refers to the “lethargy, misconception, and ignorance” of the public regarding national education. It is pertinent here to remark that when anything goes wrong and no particular individual or individuals can be held to be, or will acknowledge themselves to be, responsible, the “public” is blamed; the public being everybody with the exception of the denunciator and his friends. In the present instance the fault is not, even for the greater part, with the people. They are, naturally enough, interested in education only in so far as it is expressed in terms of school and college accounts and of wage‐earning capacity. Of the bearing that improvement in education and the advancement of physical science has on the welfare of the community the average man knows little and cares less. He has to be educated in the value of education. He is not, and probably never will be, interested in education as an abstract good. What interest he has in it is purely utilitarian. If he sees that the knowledge which he himself does not possess carries with it but doubtful prospects for the future, poor remuneration in the present and a social position little better than his own, he is unlikely to be impressed with the value of education. The fact is that there is a lamentable want of opportunity for the intellectual classes in this country and until this state of things is remedied the public will continue to display—and with every justification — “lethargy, misconception, and ignorance” in respect to national education.

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British Food Journal, vol. 18 no. 11
Type: Research Article
ISSN: 0007-070X

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Publication date: 1 August 1901

One of the commonest excuses put forward in defence of the practice of treating milk, butter, meat, and other foods with ‘preservative’ drugs no longer possesses even the…

54

Abstract

One of the commonest excuses put forward in defence of the practice of treating milk, butter, meat, and other foods with ‘preservative’ drugs no longer possesses even the appearance of validity. Several of the large railway companies are adding refrigerator vans in considerable numbers to their rolling‐stock, and this fact should make it no longer possible for defendants to plead that the necessity of sending food‐products a long distance by rail involves the necessity of mixing preservative chemicals with them. Although the excuse referred to will not bear examination, it is a very specious one, and in those instances where evidence has not been brought forward to refute it, it has produced some effect on the minds of magistrates and others. It cannot be too often pointed out that such substances as boracic acid, salicylic acid, and formaldehyde are dangerous drugs, and that their unacknowledged presence in articles of food constitutes a serious danger to the public. Such substances are not foods, and are not natural constituents of any food. In most instances they are purposely introduced into food‐products to avoid the expense attending the proper production, preparation, and distribution of the food, or to conceal the inferior quality of an article by masking the signs of commencing decomposition or incipient putrefaction, and thus to enable a dishonest producer or vendor to palm off as fresh and wholesome an article which may be not only of bad quality, but absolutely dangerous to the consumer. The use of these substances, in any quantity whatsoever, and the sale of articles containing them, without the fullest and clearest disclosure of their presence, is as gross and as dangerous a form of adulteration as any which has at any time been exposed. In no single instance can it be shown that these drugs are, to quote the words of the Act of 1875, matters or ingredients “required for the preparation or production of a food as an article of commerce,” nor, of course, can it be contended that such substances are “extraneous matters with which the food is unavoidably mixed during the process of collection or preparation.” In reality, even under our inadequate and unsatisfactory adulteration laws, through which the proverbial coach‐and‐four can be so easily driven in so many directions, there ought to be no loophole of escape for the deliberate and dishonest drugger of foods. While the presence of preservative chemicals in any quantity whatever in articles of food constitutes adulteration, wherever the quantity is sufficient to allow the production of the specific “preservative” effect of the substance added, that fact alone is enough to make the food so drugged a food which must be regarded as injurious to the health of the consumer—in view of the inhibitory effect which, by its very nature, the antiseptic must produce on the process of digestion. To our knowledge the food market in this country is flooded with all sorts of inferior food‐products which are rarely dealt with under the Adulteration Acts, and which are loaded with so‐called preservatives. There will be no adequate protection for the public against the consumption of this injurious rubbish until the consumer sees the advantage of insisting upon an authoritative and permanent guarantee of quality with his goods, and until manufacturers of the better class at length find it to be a necessity for their continued prosperity that they should supply, apart entirely from their own statements, an independent and powerful guarantee of this kind.

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British Food Journal, vol. 3 no. 8
Type: Research Article
ISSN: 0007-070X

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Publication date: 1 April 1900

The statements which have recently been made in various quarters to the effect that Danish butter is losing its hold on the English market, that its quality is deteriorating, and…

52

Abstract

The statements which have recently been made in various quarters to the effect that Danish butter is losing its hold on the English market, that its quality is deteriorating, and that the sale is falling off, are not a little astonishing in face of the very strong and direct evidence to the contrary furnished by the official records. As an example of the kind of assertions here alluded to may be instanced an opinion expressed by a correspondent of the British Food Journal, who, in a letter printed in the March number, stated that “My own opinion is that the Danes are steadily losing their good name for quality, owing to not using preservatives and to their new fad of pasteurising… .”

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British Food Journal, vol. 2 no. 4
Type: Research Article
ISSN: 0007-070X

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Publication date: 1 July 1900

A point repeatedly brought forward for the defence, or at all events for the purpose of mitigating the fine, in adulteration cases, is the statement that defendant's goods have…

62

Abstract

A point repeatedly brought forward for the defence, or at all events for the purpose of mitigating the fine, in adulteration cases, is the statement that defendant's goods have been analysed on former occasions and have been found genuine. As illustrating the slight value of analyses of previous samples may be taken the average laudatory analyses on patent or proprietary foods, drinks, or medicine. The manufacturer calculates—and calculates rightly—that the general public will believe that the published analysis of a particular specimen which had been submitted to the analytical expert by the manufacturer himself, guarantees all the samples on the market to be equally pure. History has repeatedly proved that in 99 cases out of 100 the goods found on the market fall below the quality indicated by the published analyses. Not long ago a case bearing on this matter was tried in court, where samples of cocoa supplied by the wholesale firm were distributed; but, when the retailer tried to sell the bulk of the consignment, he had repeated complaints from his customers that the samples were a very much better article than what he was then supplying. He summoned the wholesale dealer and won his case. But what guarantee have the general public of the quality of any manufacturer's goods—unless the Control System as instituted in Great Britain is accepted and applied ? Inasmuch as any manufacturer who joins the firms under the British Analytical Control thereby undertakes to keep all his samples up to the requisite standard; as his goods thenceforth bear the Control stamp; and as any purchaser can at any time submit a sample bought on the open market to the analytical experts of the British Analytical Control, free of any charge, to ascertain if the sample is up to the published and requisite standard, it is plain that a condition of things is created which not only protects the public from being cheated, but also acts most beneficially for these firms which are not afraid to supply a genuine article. The public are much more willing to buy an absolutely guaranteed article, of which each sample must be kept up to the previous high quality, rather than one which was good while it was being introduced, but as soon as it became well known fell off in quality and continued to live on its reputation alone.

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British Food Journal, vol. 2 no. 7
Type: Research Article
ISSN: 0007-070X

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Publication date: 1 June 1935

Some twenty years ago, however, the realisation came that the economy of the animal body calls for the activities of substances with functions apparently akin, in many respects at…

31

Abstract

Some twenty years ago, however, the realisation came that the economy of the animal body calls for the activities of substances with functions apparently akin, in many respects at least, to those of the hormones, which the body itself is nevertheless unable to produce, and therefore must receive them in its food. The indispensable functions of these, like those of the hormones, are adequately fulfilled by extraordinarily small amounts of each one. These food constituents yield therefore no appreciable supply of energy, nor do they serve in any ordinary sense as structural materials. Their presence like that of the hormones is necessary rather for the normal progress of active events. They have dynamic functions. I am alluding, of course, to the vitamins.

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British Food Journal, vol. 37 no. 6
Type: Research Article
ISSN: 0007-070X

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Publication date: 1 September 1901

The Board of Agriculture, by virtue of the powers conferred upon them by the Sale of Food and Drugs Act, 1899, have made regulations whereby it may be presumed, until the contrary…

51

Abstract

The Board of Agriculture, by virtue of the powers conferred upon them by the Sale of Food and Drugs Act, 1899, have made regulations whereby it may be presumed, until the contrary is proved, that milk containing less than 8·5 per cent. of solids‐not‐fat, or less than 3 per cent of fat, is adulterated within the meaning of the Act. The suggested limit for fat in milk recommended by the special committee appointed by the Board of Agriculture was 3·per cent., and it will therefore be observed that the new regulations have fixed a standard for milk‐fat which is even lower than the low limit recommended by the committee. There are even rumours that a further lowering of this standard is to bo urged upon the authorities. Although from the point of view of Public Analysts and the officials responsible for the enforcement of the Food and Drugs Acts it is satisfactory that an official standard for the composition of milk has at last been set up, it is idle to suppose that the fixing of such a limit will materially improve the character of the milk‐supply as a whole. It should be remembered that milk which contains only 3 per cent of fat, although under the new regulations legally “genuine,” is, as a matter of fact, of the poorest quality, and is only produced by a cow when in bad condition, or by a particular breed of cow which is remarkable more for the quantity than for the quality of the fluid yielded. Producers and vendors of milk of good quality have been placed in a very unfortunate position by the new regulations, as the tendency of the trade will be to lower all milk to the official limits, with the result that those dealers who are still desirous of maintaining a high standard of quality will have to compete in the matter of price with less conscientious traders, who, taking advantage of the protection afforded by the regulations, will be enabled to sell to the public “genuine” milk, from which all “superfluous” fat has been removed. Gradation of quality in an article of food cannot, of course, be provided for by official regulation, and for the purpose of legal classification it is only possible to differentiate between legally “genuine” and adulterated articles. Therefore, in a legal sense, and also in a popular sense, a milk containing 4 per cent. of fat is no more “ genuine ” than one containing 3 per cent., although the former is, of course, a superior article. Competition in the dairy trade, which has of late years become very keen, will, as the result of the fixing of this standard, become more acute than before, and to keep their position it will be necessary for those milk‐vendors who are desirous of maintaining their reputation as vendors of milk of good quality to give to their customers some guarantee that their product is indeed superior to the legalised article. Any statements of the traders themselves upon this point will naturally be received by customers with reserve, as proceeding from an interested source, and the guarantee, to be effective, must therefore be given by an authority whose statements are above suspicion. It is hero that the system of Control will be found to be a necessity both to the milk dealer and milk consumer.

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British Food Journal, vol. 3 no. 9
Type: Research Article
ISSN: 0007-070X

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