1. Pyridine promotes the precipitation of gossypol by aniline from oil solutions. A quantitative method for the estimation of gossypol in crude hot pressed cottonseed oil is outlined, which involves the use of a pyridine-aniline (4:1) reagent.
2. Samples of crude oils from six different mills analyzed from 0.049 to 0.105 per cent gossypol.
3. Gossypol in crude oils is rendered non-precipitable by heating the oil to 150° C. for 30 minutes. Heating at lower temperatures decreases the yield.
4. Photomicrographs are presented which show the crystal form of dianiline gossypol precipitated in the presence of pyridine.
This work was carried out under the direction of L. C. Haskell, to whom grateful acknowledgment is made. The writer is indebted to M. C. Kibler for assistance in conducting the analyses.