The first able memoir which contested all that has been said in favor of inoculation, appeared in Turin, and was written by Dr. Riviglio, a Piedmontese veterinary surgeon. This was supported by the views of many others. Prof. Simonds wrote against the plan, and, in 1854, the French commission, whose report has been before mentioned, confirmed, in part, Riviglio's views, though, from the incompleteness of the experiments, further trials were recommended. Inoculation is performed as follows: A portion of diseased lung is chosen, and a bistoury or needle made to pierce it so as to become charged with the material consolidating the lung, and this is afterward plunged into any part, but, more particularly, toward the point of the tail. If operated severely, and higher up, great exudation occurs, which spreads upward, invades the areolar tissue round the rectum and other pelvic organs, and death soon puts an end to the animal's excruciating suffering. If the operation is properly performed with lymph that is not putrid, and the incisions are not made too deep, the results are limited to local exudation and swelling, general symptoms of fever, and gradual recovery. The most common occurrence is sloughing of the tail; and in London, at the present time, dairies are to be seen in which all the cows have short-tail stumps. Dr. Williams and others have gone too far in attempting to describe a particular corpuscle as existing in the lymph of pleuro-pneumonia. All animal poisons can be alone discovered from their effects. In structure and chemical constitution, there is no difference, and often the most potent poisons are simple fluids. The Belgian Commission, appointed to investigate the nature and influence of inoculation for pleuro-pneumonia, very justly expressed an opinion that Dr. Williams had not proved that a specific product, distinguished by anatomical characters, and appreciable by the microscope, existed in this disease. The all-important question, "Is inoculation of service?" has to the satisfaction of most been solved. The Belgian and French commissions, the observations of Riviglio, Simond, Herring, and many others, prove that a certain degree of preservative influence is derived by the process of inoculation. It does not, however, arrest the progress of the disease. It certainly diminishes to some extent--though often very slightly so--the number of cases, and, particularly, of severe ones. This effect has been ascribed to a derivative action, independent of any specific influence, and, indeed, similar to that of introducing setons in the dewlap.