"Considering," continues Dr. Stanley, "the usual excessive mortality during an outbreak of this disease, the result may almost be compared to the success of vaccination against small-pox. Three young bullocks, each having received 20 cubic centimetres of cattle-plague gall, were purposely exposed to severe infection. They remained well, while unprotected animals around them died of the disease." In the domain of immunity there is, however, no more fascinating or interesting story than that which deals with the discovery and elaboration of a cure for snake-bites, a discovery which, while attracting but comparatively little attention in this country, should prove of paramount importance to our fellow-subjects in the great Indian Empire. The significance to India of Professor Calmette's discovery of a specific cure for snake-poison may be gathered, indeed, from the statistics which have been compiled of the number of deaths attributed by Indian officials to this cause alone, amounting, it is said, to some 22,000 annually. The Pasteur Institute in Paris has despatched many pioneers of science to various quarters of the globe, but perhaps no scientific missionary has produced more fruitful results than has Dr. Calmette. It was while acting in the double official capacity of Médecin de 1st Classe du Corps de Santé des Colonies and Director of the Bacteriological Institute of Saïgon, in Cochin China, in the autumn of 1891, that Calmette first commenced his experiments on the neutralisation of serpent venom in the animal system. He had, indeed, exceptional opportunities in the matter of serpent venom wherewith to carry out his investigations, for during the rainy season a village in the neighbourhood of Bac-Lieu (Cochin China) had been attacked by a band of most venomous serpents. These creatures, driven by the floods into the very huts of the natives for shelter, created a terrible panic, and no fewer than forty individuals were bitten by them. The panic was certainly not without justification, for these serpents belonged to the species known as _naja tripudians_, or _cobra de capello_, renowned for the deadly nature of their venom, and widely distributed over India, Burmah, Sumatra, Java, Malacca, and Cochin China; but until Calmette set to work to systematically study the nature of this reptile's venom but little precise or reliable information had been obtained as to its character. The governor of the district gave orders that as many as possible of the reptiles were to be captured alive and forwarded to the Director of the Bacteriological Institute, and a plucky Annanite actually succeeded in securing ninety specimens, which were forwarded in a barrel to Dr. Calmette. This formidable gift was received with enthusiasm by the director, who realised the importance and scope of the inquiry, which he at once set himself to systematically work out.