Sodium sulfide is an organic chemical that has attained an important position in the organic industry. It is consumed as a reducing agent in the manufacture of amino compounds, and it enters into the preparation of many dyes. It is also employed extensively in the leather industry as a depilatory. Sodium polysulfide is one of the important are the rayon, metallurgical, photographic, and engraving fields. This product usually is a side product of other industry. This chemical may be obtained as 30% crystals of sodium sulphide or as 62% flakes. Solutions of it may be shipped in steel. One disadvantageous property of sodium sulphide is its deliquence. It crystallizes wit nine molecules of water, Na 2 S.9H 2 O. The oldest method of production is the reduction of sodium sulphate with powdered coal in a reverberatory furnace. Another similar process is the reduction of barite in the same manner, leaching and double decomposition with soda ash. For the reaction involving the reduction of s...