The briefed findings are from 20-year laboratory, lysimeter, and pot-culture experiments on the chemical and biochemical behavior and the fate of fluorine after it reaches soils through insecticides, fertilizers, cryolite, rock phosphate, various fluorides and silicofluorides, slag, and rain waters, and from the atmosphere, and in particular the migration of the element from soil into vegetation. Through collaboration with TVA and two major manufacturing corporations, the experiments were elaborated to include studies of injurious effects upon plant and animal life purportedly resultant to fluoric effluents from two manufacturing operations in two widely separated locales in Tennessee. Soils were found to possess remark-THE utility of fluorine compounds as dusts and sprays for insect control on field crops long has been under study at The University of Tennessee {52). Virtually nothing was known, INDUSTRIAL AND ENGINEERING CHEMISTRY Vol. 41, No. 11 Uniformity in Growth of Soybeans initial crop) after identical inputs of fluorine, 300 pounds per 3,000,000 pounds of limestoned Hartsells fine sandy loam (top row) and of limestoned Clarksville silt loam (bottom row) at Knoxville A, Magnesium fluoride 3. Sodium fluoride C, Sodium silicofluoride D. Untreated