During the last few years considerable data have accumulated concerning the sulphur content of rainwater. No doubt much of the interest in this subject has arisen because of a desire to ascertain how far the sulphur in rainwater would go in making up what many thought was a present or coming agricultural deficiency of this element in the soil. In table I we have summarized some of the data on this subject. The data of table 1 show a great variation in the sulphur content of rainwater falling at different places. The influence of coal consumption is clearly shown. For example, the sulphur content of rainwater falling at an industrial city such as Leeds, England, or Knoxville, Tenn., is much greater than that of a purely agricultural section such as Ames, la. The data for Mt. Vernon, la., show that the amount of sulphur brought to the soil by the rain may vary decidedly from year to year. The data of table I will be referred to again in connection with the discussion. During the years 1921-1923 we made analyses for sulphur of rainwater collected at Chicago, 111., and near Liberty, Indiana. The station in Chicago was located at the University of Chicago campus. Liberty is a town of about 1,300 inhabitants, with hardly any manufacturing. The station was located about four miles northeast of the town. Richmond, a town of about 27,000 population and with considerable manufacturing, is located about thirteen miles slightly west of north of the station. Thus the data should give a good comparison of a great industrial and residential center, and a typical agricultural section.