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both for routine commercial testing in dairy factories and grading stores, and for analytical work in laboratories generally. Sampling and Chemical Analysis of Cheese.—The foregoing report relating to sampling and chemical analysis of butter applies equally to a similar draft standard specification for the sampling and chemical analysis of cheese. Acidity in Cream, Milk, and Whey. —A standard specification for solutions and methods for the estimation of acidity in cream, milk, and whey was completed and printed in 1940, but its issue was held in abeyance on account of the difficulty in obtaining supplies of phenolphthalein for making up the stronger solution, which was specified in order to obtain more accurate test results. With some minor amendments, the standard specification has now been issued, and, since the determination and control of acidity is a primary factor affecting the quality of both butter and cheese, it will be of paramount importance in that it will serve virtually as a text-book which, within practical limits, will eliminate variation in testing methods and practice followed by different operators in dairy factories and elsewhere. Gerber Method for determining Fat in Milk. —Following a detailed investigation, the Dairy Products and Requisites Committee has recommended the British standard for this test for adoption as a New Zealand standard specification, subject to local amendments. The adoption of the standard will ensure that accurate and comparable results are obtained by analysts, dairy instructors, factory-managers, and herd-testers, to whom it will be a valuable text-book. Babcock Method for determining Fat in Milk. —Experience in New Zealand has shown that the British standard for this test is not entirely satisfactory for New Zealand requirements. Research has therefore been carried out by the members of the Dairy Products and Requisites Committee to establish the requirements relating to the technique and apparatus for the Babcock test that will satisfy New Zealand conditions, and the committee is collaborating with the American Dairy Science Association in long-range research on this subject. It has drafted an extensive amendment and addendum to the British standard which, subject to these amendments, has been recommended for adoption in New Zealand. Reductase Test on Milk.—The draft New Zealand standard specification for the reductase test on milk, which is used to determine its keeping and hygienic quality, has been circulated to the affected interests, and their comments have been assembled for consideration by the Dairy Products and Requisites Committee. Alkaline Cleaners.—The proposed New Zealand standard specification for alkaline cleaners (excluding soaps) is nearing the draft stage. The initial drafting of the specification was carried out by a joint panel of the Dairy Products and Requisites Committee and the Chemical Sectional Committee. It will provide a basis for the sale and purchase of dairy detergents on the basis of their efficacy in relation to price and in relation to their suitability for the different purposes for which they are required, which the experience of factory-managers has shown to be necessary. For example, investigation has shown that the use of corrosive detergents is frequently the cause of premature rusting of dairy tinware and milk-cans. Other Projects.—The committee is also giving attention to coated tinfoil; anatto and other dyes ; cheese-cloth, butter-muslin, cheese-bandages, and cheese-caps ; quality of casein for different purposes ; estimation of visible dirt in milk ; sampling of all dairy products ; bacteriological analysis of dairy products ; butter-wrappings ; coagulating strength of rennet; acid and rennet casein ; salt for dairy purposes; and floating protected dairy thermometers. Milking-machine Rubberware. —The emergency standard specification for Milkingmachine Rubberware has been revised and will be reissued as a regular standard specification. Milk-bottles.—A committee was instituted to formulate a standard specification for milk-bottles, which will establish uniform requirements in respect of essential

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