Methods of Rapid Determination of Moisture Content of Wood

°°1. The methods employed for the rapid determination of moisture content of wood are based on four diiierent principles, namely :- (i) The change in relative humidity of air in the immediate neighbourhood of the piece of wood to be tested. (ii) The distillation of the specimen with an organic liquid immiscible with water, having a boiling point between l0O° C. and 150° C. (iii) The change inthe electric resistance of wood with variation in its moisture content. (iv) The change in dielectric constant of wood caused by the presence of moisture. The advantages and disadvantages of the various methods are. discussed. 2. The electric resistance method is the most convenient to employ and within the range 7 per cent. to 24 per cent. moisture content, the results obtained on Indian woods with the Tag-Heppen- stall moisture meter are very satisfactory. 3. A correction table is given for some of the more common Indian woods for applying to the readings of the Tag-Heppenstall moisture meter. 4. A method is described for determining the moisture gradient in thick timbers with the Tag-Heppcnsta]l moisture meter by the use of steel nails.