There is published in the May number two monographs: The first upon "The Preventive Treatment of Calculous Disease and the Use of Solvent Remedies," by Sir Henry Thompson, F.R.C.S., M.B. The author states that we have the power to check the production of calculous matter at almost any stage of the complaint, and can almost certainly render its formation impossible if proper treatment be adopted. The dietetic treatment, upon which success largely depends, and the value of mineral waters are then fully discussed. The best, however, that modern science has done toward the solution of uric acid concretions, which are the basis of more than 90 per cent. of all calculi, is founded upon the use of potassium carbonate and the author unites with Sir William Roberts in agreeing that this is the most powerful solvent known, much better than either salts of sodium or lithium, Finally, it is necessary