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doubt that wooden buildings, without the use of treated timber except in a few parts, will give a much longer life than is required either under any system of loan retirement or to keep abreast of changing living-conditions from century to century. 3. Research. (a) Timber Mechanics. The detailed data regarding the mechanical and physical properties of the principal indigenous and exotic timbers now possessed by the State Forest Service as the result of a comprehensive series of tests completed several years ago continues to find an ever-increasing field of usefulness. The results of these tests have been applied during the year to the selection of timbers for numerous specialized purposes ranging from clothes-pegs and miscellaneous handles to aeroplane-construction. There are few wood uses in which serviceability is not in some way related to one or more strength properties, and the accurate knowledge which is available on the strength of the various woods in bending, compression, and shear, their toughness, rigidity, and other factors determining their resistance to all kinds of stresses, makes the data invaluable to wood users. The further fact that the results of the tests are directly comparable with those of similar tests on practically all the world's most important timbers makes them of pertinent value in selecting locally-grown substitutes^ for imported timbers, and the ever-increasing inquiries received in this connection- have ranged from door and furniture core-stock to meat-cases. The work now being carried out by the New Zealand Standards Institute to unify and improve building by lows hn.n also brrn fncilitatorl in respect to light wooden construction by the data available on building-timbers. (b) Timber Physics. Requests for the identification of timbers continue to increase, and the reference set of microscopic slides built up during the last ten years, and now amounting to several thousand, has proved invaluable in expediting identifications. With the increased use of wood by secondary industries the question of moisture content has become of paramount importance to both the timber trade and to wood-users. In many circumstances it is still necessary to resort finally to the oven-drying method of determining moisture content, but the slowness of this method has served to concentrate more and more attention upon the possibilities of using the various types of electrical moisture meters which have been developed during recent years. Tests of both the inductance and capacity type of moisture meter are now in progress, and the preliminary results indicate that the modern equipment has been developed to a point where its reliability and ruggedness warrants its application for many purposes, and reputable makes of various types can now be widely recommended. The principal kiln-drying investigation undertaken during the year was one to study the possibilities of kiln-drying framing timbers, but, not unexpectedly, the inherent difficulty of drying without distortion the usual grade of scantling stock containing fairly large defects has proved uneconomical. Of far-reaching importance has been the success achieved in the preliminary salt seasoning of locally-grown eucalypts and larch, posts and poles. The excessive splitting of New Zealand eucalypts and larch under ordinary conditions of seasoning has hitherto proved a serious detriment in respect to their strength, but the immersion of the green timber in a strong solution of salt has given sufficiently promising results in the elimination of this checking to justify the extension of the tests on a commercial scale, and a large number of eucalypt poles and posts have been so treated at Rotorua preparatory to creosoting (Plates Nos. 21-22). (c) Wood Preservation. Improved laboratory facilities have made possible an increasing amount of valuable experimental work on several branches of wocd preservation, including general diagnostic work, testing of preservatives, and paint research.

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