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378 mitters of the Bacillus typhosus, they are almost sure, sooner or later, to fall victims.

It would appear that typhoid is not only a common disease among Europeans in the tropics, but that it is also a very virulent one, with a death-rate twice as heavy as the death - rate of typhoid in England. According to my experience in China, not only is the tropical form grave from the outset, but it is extremely liable to relapse. In England the death-rate is put down at about 1 in 8 attacked; but in India the elaborate and carefully prepared statistics show a death-rate of rather over 1 in 3. Typhoid in India, indeed, kills more European soldiers than does cholera. Not only does typhoid exhibit increased virulence, but experience has shown that against it those sanitary safeguards which are found to be practically sufficient in England are by no means so effective in India. It would also appear that soldiers on the march contract the disease in passing through uninhabited country, in spite of the fact that the camp may be pitched in spots which, presumably, had never been occupied by man before, and although the men may have drunk only of water from springs and streams that were beyond suspicion of fsecal contamination. Similar testimony comes from Australia, where typhoid has occurred in the back country in lonely spots hundreds of miles from fixed human habitations. These data suggest that typhoid carriers are more numerous and varied than is generally believed, or that Eberth's bacillus, under certain conditions of soil and temperature, may exist as a pure yet virulent saprophyte, for which an occasional passage through the human body is not necessary. Anti-typhoid inoculation.— Having observed that injection into the subcutaneous tissues of the human subject of dead cultures of Bacillus typhosus conferred on the blood of the individual experimented on the power of agglutinating and sedimenting living cultures of the bacillus, Sir A. Wright, in the hope that in this circumstance he had grounds for concluding that protection against typhoid might be conferred