Neuberg states that Berlioz and Lepinois, and other French writers found chlorine present in urine partly in organic combination. Later investigators denied this. Baumgarten obtained results indicating that 0.04 to 0.2 gm. of organic chlorine is excreted daily in the urine; the maximum found amounted to about 10 per cent of the total chlorine excretion, and was independent of the amount of sodium chloride in the diet and the temperature of the individual. We have been unable to find any more recent work dealing with the possible presence of organic chlorine in urine. Baumgarten's method consisted in treating urine with sodium nitrate and fuming nitric acid (to reduce chlorates), adding excess of silver nitrate and filtering in darkness, and, after removal of excess silver, concentrating to one-third, again filtering, and heating the filtrate in a retort with concentrated nitric and sulfuric acids free from chloride. The distillate was collected in a dilute silver nitrate solution, and silver chloride was precipitated in this corresponding to the amounts of chlorine indicated above. This chlorine was considered to be in organic combination. we have repeated Baugarten's procedure with completely negative results. Chlorates and perchlorates do not appear to occur normally in urine, and when administered are excreted in the urine unchanged and almost quantitatively within 48 hours. We have confirmed the absence of chlorine-oxy-acids from normal urine by the following procedure...