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282 think that success in this sphere of action merely indicated that the prize-man had the ability and skill to get on in an examination. No doubt a stupid and idle man could not get first places in examinations, and so the industrious and clever were picked out by the process. But it was certainly not the case that those who failed to get the highest honors in examinations went to the wall in after-life. On the contrary, he was sorry to say that he knew some who had succeeded to the fullest extent during the examinational period of their life, yet did not maintain their prestige as time rolled on. And not a few men who were signal failures at examinations have proved of enormous value in after-years. To some a vast amount of evil was wrought from the fact that no proper knowledge had been acquired to pass the standard. He advocated a plan of examination which is partly carried out at the School of Science, South Kensington. That was, to study and be examined on each subject separately, and by the same persons who had acted as teachers.

The Future of Physiological Experiment.—Professor Tyndall founds a new argument in favor of the practice of experimental physiology in the peculiar properties of infectious diseases, and their probable germ origin. One of the most extraordinary and unaccountable experiences in medicine has been the immunity secured by a single attack of a communicable disease against future attacks of the same malady. Small-pox, typhoid, and scarlatina, have been found, for example, as a general rule, to occur only once in the lifetime of the individual, the successful passage through the disorder seeming to render the body invulnerable against future attacks. Professor Tyndall had some time ago suggested to a friend that the phenomenon could be explained under the germ theory by supposing the soil, or the system, to be exhausted by the first parasitic crop, of some ingredient necessary to the growth and propagation of the parasite. Some important essays on the subject have been recently published in the "Revue Scientifique" by M. Bouley, who draws attention to the results obtained by M. Raulin in the cultivation of the microscopic plant Apergillus niger. The omission of potash from M. Raulin's liquid suffices to make the produce fall to one twenty-fifth of the amount collected when potash is present. The addition of an infinitesimal amount of a substance inimical to the life of a plant is attended with still more striking results. For example, one part in 1,600,000 of nitrate of silver added to the liquid entirely stops the growth of the plant. Now, supposing the aspergillus to be a human parasite—a living contagium—capable of self-multiplication in the human blood, and of so altering the constitution of that liquid as to produce death; then, the introduction into the blood of a man weighing sixty kilogrammes, of five milligrammes of nitrate of silver would insure, if not the total effacement of this contagium, at all events the neutralization of its power to destroy life. An index-finger here points out to us the direction which physiological experiment is likely to take in the future. In anticipation of the assault of infectious organisms, the experimenter will try to introduce into the body substances which, small in amount, shall so affect the blood and tissues as to render them unfit for the development of the contagium. And, subsequent to the assault of the parasite, he will seek to introduce substances which shall effectually stop its multiplication. Dr. Polli, of Milan, has already obtained results that promise well with alkaline sulphides in certain fevers and small-pox, and Crudelli obtained similar results with arsenic against the malaria of the Roman Campagna. To enable us to administer these remedies safely and with some assurances of success, experiments must be made of their effects, on different groups of individuals, and these individuals must be animals susceptible to the infection and to the counteracting application. "I appeal," says Professor Tyndall, "not to the partisans of either side, but to the common sense of England, whether, in the interests of humanity, the proposed experiment is not a legitimate one."

Effect of School-Work on the Brain.—A question was recently asked Mr. Mundella, in the British House of Commons, as to the effect of the English educational system on the health of children and teachers. He replied in substance, availing himself of the reports of the Lunacy Commissioners,