It is still an open question whether or not wood placed in contact with alkaline soils has a longer or a shorter life than wood placed in contact with ordinary soils. Since there are enormous areas throughout the West in which the soil is more or less alkaline, and since relatively large amounts of wood in the form of railroad ties, fence posts, telegraph posts, wood pipe, flumes, etc., are continually in contact with such soil, the question is one of considerable importance. The action of alkaline soils upon wood may be either direct or indirect. By a direct effect is meant the chemical action of the salts composing the soil upon the wood. The only salt found in alkaline soils that need be considered in this connection is sodium carbonate or sodium bicarbonate. Sodium chlorid and sodium sulphate, the other important component salts of soil alkali, have no important chemical effect upon wood substance or structure. The action of any strong base upon wood is well known, but whether or not the concentration of sodium carbonate or bicarbonate ever becomes great enough in an alkaline soil to injure chemically wood in contact with it is more or less a matter of conjecture, although there seems to be a priori some evidence in favor of the affirmative side of this question. It is obvious that, if wood that is saturated with the soil solution of any alkaline soil containing sodium carbonate or sodium bicarbonate in considerable amounts should gradually dry out, the concentration of the salt would gradually increase with the evaporation of the solvent until the solution became quite concentrated. It is conceivable that a constant repetition of this process may have an ultimate effect on the wood. It is not, however, the purpose of this paper to consider the direct effect of alkaline soils upon wood placed in contact with them. The present paper considers only the indirect effect of the salts making the alkali of alkaline soils upon wood. By an indirect effect is meant