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LEATHER AND SHOE RESEARCH Director: Mr. P. White. Assistant Director: Mr. F. G. Caughley Leather Research Association Advisory Committee. —Messrs. A. E. Lawry (Chairman), C. Arlington, J. E. Astley, S. L. Wright, R. L. Andrew, and F. Johnson. The war has brought about many significant changes in the leather industry. The demand for heavier types of leather, in much larger quantities than ever before experienced, has created many difficulties. Not only has the quality of the leather to be maintained, but the tanner is faced with difficulties of expansion, supplies of raw materials, man-power, reorganization of processes, and, above all, output. The future or the post-war period has also to be considered if the industry is to maintain its position in the economic life of the community, and the post-war problems can be faced with greater confidence by the possession of a greater knowledge of the fundamental facts of leather manufacture and how these affect the desirable characteristics of leather. Sole Leather.—During the past year an investigation has been commenced on the involved question of flexibility of sole leather. In recent years the public have demanded that footwear shall provide a reasonable degree of foot comfort, sometimes irrespective of wearing value. The increasing demand for comfort requires that the soles shall be sufficiently flexible so as to interfere as little as possible with the natural movements of the muscles of the foot. Quality in solo leather is a summation of several features, the chief of which are resistance to water absorption, resistance to wet and dry abrasion or wear, and flexibility. In order to obtain the best total summation, compromises have to be made. It _is nectessary, therefore, to obtain detailed information on each of these individual qualities before a decision can be made as to how far the compromise is justifiable. Some factors affecting the flexibility of sole leather have been determined during the year and to some extent, have been correlated with water absorption. In addition, the usual routine work of checking factory processes, materials, and finished leather have been carried out. Shoe Research Association Advisory Committee..—Messrs. W. Denby, P. E. Edwards, W. S. Livingstone, D. I. McDonald, and R. L. Andrew. Flexibility of Sole Leather. —The shoe industry is very much concerned with other aspects of the quality of sole leather than those mentioned above. In the first case it is very desirable that sole leather shall be reasonably easy to work in the shoe-factory. This implies that the leather must temper properly, must mould to the shape of the last, channel properly, must not be too difficult to sew, and must be able to hold tacks or screws. On the other hand, the shoe manufacturer's reputation depends on the wearing value and comfort of his products. Here, again, compromise is necessary, and the justifiability of the compromise can only be determined by a fuller knowledge of the relationships of the qualities of sole leather. Adhesives. —Owing to further curtailments in the supply of rubber and nitrocellulose cements during the year, the position with regard to adhesives became more acute. This was lessened to some extent by the increased production of footwear for the armed forces. Rubber, with its unique properties, makes an adhesive for which no simple substitute has as yet been found. The position in regard to water adhesives and pastes is different, and little difficulty has been experienced in meeting the requirements in these lines. Factory Problems.—That the Research Association has the confidence of the industry is shown by the number of problems submitted for examination during the year. The discussion of these in the monthly circular letters and with the staff on the occasion of visits to the shoe-factories has fully maintained the interest in the work of the Research Association. MINERAL CONTENT OF PASTURES INVESTIGATIONS AT THE CAWTHRON INSTITUTE Introduction During the past year cobalt investigations have been continued at Sherry Valley, these comprising an animal trial under different conditions of top-dressing of the pasture and an examination of the cobalt content of mixed pasture following the use of various cobaltcontaining fertilizers. Animal organs from an earlier experiment at Glenhope have been analysed. Animal Trials At Sherry River the hoggets on areas top-dressed with the equivalent of 2 oz. and 4 oz. cobalt sulphate per acre have been retained on these areas for a further season. Another application of 2 oz. cobalt sulphate was given this last spring (1942).

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