The specific volume of the different constituents of green woods has been estimated by M. Hartig to be as follows, per 1,000 parts: Hard green wood, fiber stuff, 441; water, 247; air, 312. Soft green wood, fiber stuff, 279; water, 317, air, 404. Evergreen wood, fiber stuff, 270; water, 335; air, 395. A certain amount of water--7 or 8 per cent in all--is included with the fiber stuff, showing that about one-third only of the mass of the wood is solid stuff; the remainder is either water or air space.