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The rate of burning of wooden dowels injected into the centre of various test fires was determined by direct weighing. The curves giving the rate of burning vs. time of exposure are presented for dowels of length 88.9 mm and diameters ranging from 2.54 mm to 50.8 mm. Five types of wood: birch, oak, pine, cedar, and balsa, were studied. The time of exposure to produce 80% mass loss was found to be proportional to the diameter of the dowel raised to a power varying between 1.3 and 1.5 depending on the type of wood. The average rate of mass loss per unit initial mass for the wooden dowels during the exposure was found to be inversely proportional to the initial diameter to the 1.5 power for the five woods investigated. The maximum rate of mass loss per unit initial area for the wooden dowels during the exposure was found to be essentially independent of initial diameter for dowels above 10 mm.