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A partial review of published experiments which appeared to have a bearing on this subject was compiled by two of the present w'riters in 1913 (4). 3 In this review, results were grouped under two headings; (a) experiments showing higher nitrate content under plants than in fallow land, (b) experiments indicating a depressed nitrate formation under plants. It is significant that the soils in which it was found that the nitrate content under living plants was higher than in similar soil under fallow were all made during the earlier stages. of growth of the plants and that the analyses that indicated a. depressed nitrate formation were all made at a later stage or at maturity.A short time afterwards Russell (7) reported some experiments on this subject and also reviewed some of the literature. His own experiments, and most of those which he cited, indicated only a depressed nitrate formation in soil bearing plants.It should be noted that with the exception of those which did not indicate a depression of nitrate formation by the crop all of the analyses reported by Russell were made when the plants had reached maturity.Russell cited an investigation by \Varington (9) who found an apparent disappearance of nitrate nitrogen on cropped land. \Varington suggested that the crop may have taken up this nitrogen and afterwards lost it, presumably to the air. Russell, howeyer, holds that the disappearance of nitrate nitrogen in the cropped soil is more properly to be attr~buted to diminished production and further that the diminished production is not to be traced to the effect of the crop 10n the 'temperature ot: moisture content of the soil.Beside the theory advanced by Vvarington to account for the disappearance of nitrates in soil accompanying the growth of plants, one has been proposed by Deherain (r) to the effect that the growing plant by removing moisture from the soil

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For a number of ye~rs the rainwater at Ithaca, New York, has been collected and analyzed monthly and semi-annually for nitrogen and sulfur respectively. ~eports (3, 4) 3 of this work with rather extended bibliographies have appeared in the literature.It is the purpose of the present paper to bring together the data which are now available for Ithaca and also those for two other collecting stations, one located at Brockport, New York, and one at Alfred, New York. 4 The rainfall from these last two stations was analyzed for sulfur semi-annually. Nitrogen was determined for periods so arranged that certain of them included the collections for one-half of the year beginning with May, while other collections covered the remaining portion of the year.At each of. these stations the precipitation was collected in an 8inch gauge. After each rain or snow its contents. was emptied and the water stored, until analyzed, in a glass bottle containing a few drops of a saturated solution of mercuric chloride. The samples of rainwater were analyzed for ammoniacal nitrogen by the Nessler reaction as used in water analysis and for nitrate nitrogen by the phenoldisulfonic-acid method. Sulfur was determined by evaporating r-liter samples of the filtered water, both with and without the addition of an oxidizing agent. The sulfur, all of which was found to be in the form of sulfate, was finally ·weighed as BaS04. NITROGEN IN RAINWATER AT ITHACAThe gauge used for collecting the rainfall at Ithaca is located in a cultivated field and stands about 9 feet from the gr:ound. In a previous paper (3) it is stated that this field is in an area comparatively free from smoke. Since then a large heating plant has been constructed within a mile of the field. While its operation, since the fall of 1923, has increased materially the smoke in the vicinity of the gauge, it has not caused the nitrogen in the rainwater to be consistently higher than that found in years prior to its construction.

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