27

C.—3

Studies under Way and Investigations. Altogether over thirty major investigations are in progress. These include : Sawmills and "woodwaste survey; introduction of shop grades into New Zealand grading rules ; wood requirements of wood-using secondary industries ; statistical survey of sawmilling industry ; woods for butter-boxes ; uses for short lengths of timber ; standardization of sizes, grades, and nomenclature for yard timber ; utilization of little-used species ; study of floating properties of New Zealand woods ; physical properties of wood ; air-seasoning of wood ; basic mechanical properties of woods grown in New Zealand ; grading rules and working-stresses for structural timbers; cross-arm tests ; routine strength tests of plywood ; test of box-bindings ; study of nail-holding power of New Zealand woods ; treatment of wood by non-pressure process ; treatment of wood by pressure process ; service-test records ; routine examinations of wood-preservatives ; the pulping of thinnings from Rotorua plantations ; suitability of New Zealand woods for pulp; microscopic structure of woods; kauri-bleeding; relation between durability and the chemical composition of woods ; destructive distillation of native and exotic woods ; prevention of sap-stains and moulds on timber ; relative resistance of untreated woods to borer-attack; relative resistance of untreated woods to decay ; introduction of forest and timber insects and fungi in imported forest products.