To six 50-gm. portions of sieved soil,50-cc. portions of 2.5% NaOH are added. The flasks are auto-claved 30 min. at 15 pounds or allowed to stand for 48 hours in the cold. The solution is then filtered. Fresh 50-cc. portions of 2.5% NaOH are added to the soil and extraction is repeated. The 2nd extract is filtered through the same paper. The soil is then thrown upon the paper and washed first with 2.5% NaOH, then 2-3 times with distilled water, until the solution comes through quite clear. The combined filtrate is treated with 10% warm HC1 until a heavy precipitate is formed; \ as much more acid is then added and the flask shaken. A part of the precipitate may go into solution. The precipitate left is filtered through a weighed dry filter paper or a Gooch crucible, washed several times with 2% HC1, and then several times with distilled water. The precipitate is dried at 65-70[degree]C. for 12-24 hours and weighed. Three portions of the precipitate are used for determination of ash and 3 for total N. The filtrate from the 1st precipitate is treated with 2-3% NaOH, until a precipitate begins to form; the alkali is then added drop by drop to obtain maximum precipitation, avoiding an excess of alkali. This 2nd precipitate ([beta]) is also filtered through weighed dry papers or Gooch crucibles; the filtrate is tested with a drop of acid and of alkali to see that no further precipitate is formed. If it does form, the filtrate is again adjusted and the new precipitate added to the 1st. This precipitate is washed repeatedly with distilled water, dried at 90-100[degree]C, and weighed. Two portions are used for ignition, 2 for total C, and 2 for total N determinations. The liquid from the [beta] precipitate, which should be straw colored, is used for determining total N and C in solution. In peat soils, only 5 gm. portions of dry soil are used, and treated twice with 50 cc. of 5% NaOH as before.