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380 the non-inoculated. The results were better after a single than after a double inoculation, which appeared, according to Crombie's figures, to increase the liability to infection.

Since the time Crombie's statistics were compiled, anti-typhoid inoculation has been practised not only in the army in India, but also by the French in their armies in Tunis, Algeria, and Morocco, and by the Americans on the Mexican boundary, with gratifying results. These results have been amply confirmed by the extensive use of inoculation against typhoid during the Great War. Better methods of preparation and dosage have been introduced, and the reaction after vaccination has been mitigated thereby. According to Leishman, the rule is to use a vaccine not over three months old, to give two doses, the first containing 500 million bacilli, and ten days later the second of 1,000 million bacilli. The average duration of protection he considers to be two years, after which one injection of 1,000 bacilli should be given.

Details of the method of preparation and of the clinical effects of Sir A. Wright's inoculations will be found in the Lancet of September 19, 1896, and the British Medical Journal of January 20, 1900. It is not requisite to enter further into the subject of typhoid fever, for, although this important disease is abundantly common in the tropics, it is not properly classifiable as a tropical disease; moreover, it is fully dealt with in every textbook on general medicine. It is alluded to here rather by way of warning the practitioner in the tropics against overlooking it, and against assuming that every case of fever he may encounter is malarial; and, also, of indicating the special importance to him of a knowledge of the latest views on the practical value of anti-typhoid inoculation.

Some years ago a good deal was said, particularly in America, about " typho-malarial fever." An idea got abroad that there is a specific disease which, though resembling both, is neither typhoid nor