PIPERAZIN AND PIPERAZIN HYDROCHLORATE. I have of late had ample opportunity to test both piperazin and piperazin hydrochlorate as solvents of uric acid. Hitherto I have used the salts of lithium and potassium in the uric acid diathesis, but will now certainly always use the new solvent in preference to either of these. I have taken particular pains to watch the action of the drug—so feel confident in stating that it is the best of known uric acid solvents. I have never noticed any toxic effects from the use of either preparation, but prefer the hydrochlorate on account of being less hygroscopic, although I believe piperazin can now be procured in lozenge-form in glass tubes, which greatly lessens the hygroscopicity. I will now briefly give particulars of three cases of uric-acid diathesis treated with the medicine. The first, a man aged 36, weight, nearly three hundred pounds, suffered much renal pain, with occasional symptoms of small calculi passing along ureter. The urine had very acid reaction. The microscope revealed numerous crystals. The murexide test likewise proved that uric acid was present in abundance. This patient, wishing to become thin, was put on a beef diet, no potatoes, few vegetables, etc., just the diet to increase the uric acid. He was put on the solvent treatment, giving twelve grains, divided into three doses daily. Each dose was given in a tumblerful of vichy water. In a few days the urine became neutral in reaction; the loin-pains left; also the constant desire to micturate caused by the irritation of the uric acid. The beef-treatment was kept up for several weeks and the weight was reduced by 11 pounds. This case shows that, although no precautions were taken to diminish the formation of uric acid, but the contrary, piperazin was sufficient to dissolve the crystals. The second case was that of a man aged 50, weight, 215 pounds. He complained of pain, described as “burning” in loins; also a dull ache in bladder, frequent desire to micturate; sometimes urine was mixed with blood. Without altering the diet at all, which was always a liberal one, including beer every day, all the disagreeable symptoms disappeared while taking piperazin hydrochlorate. On several occasions there was a return, in a modified form, of the symptoms, but after a few doses of the drug they always disappeared. The third case was that of a man 60 years of age, who had for years felt pain in kidneys, along ureter and in bladder, and never got much relief. I prescribed for him 5 grains of piperazin to be taken three times daily in large quantities of water. After a week’s treatment the pains had left, and he was better than he had been for years. Gruber has used it with good results in diabetes. He considers that the action of the drug in this disease is inhibitory to the transformation of glycogen into sugar. HYPODERMATIC ALIMENTATION.