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356 cotton-wool (16 by 12 cm.) enclosed in muslin, and retained in position by a many-tailed gauze bandage, together with goggles, rubber gloves, and cotton uniform, proved thoroughly effective.

Haffkine's inoculations.— Early in the Bombay epidemic Haffkine introduced a system of prophylactic inoculation which is of proved value, both in reducing the number attacked with plague to the extent of from 77 to 85 per cent., and also in diminishing the mortality in those attacked by 80 per cent.*

It consists essentially in the subcutaneous injection of six-weeks-old cultures of plague bacilli incubated at 25°-30° C. and killed by heat 65° C. for one hour; carbolic acid, 0.5 per cent., is then added. The reaction is at times severe, but until quite recently no grave accident had occurred. The figures are not so favourable for Mauritius, where inoculations reduced the plague incidence to. the extent of 45 per cent, only, and the mortality in those inoculated to 32.9 per cent. The Indian Plague Commission reports strongly in favour of these inoculations. All plague laboratory workers and all who are likely to be exposed to plague infection should receive them. The protection they confer lasts about twenty months. In the report of the Bombay Bacteriological Laboratory, 1911, Glen Liston states that in the inoculated the incidence of plague was 8 per 1,000 of the population concerned, whereas it was 34 per 1,000 in the uninoculated in the same communities; the case-mortality in the inoculated was 39-5 per 1,000 attacked, in the uninoculated 78 per 1,000. The best results were obtained from a two-months' growth which had been stored about eighteen months. The prophylactic needs great care in its preparation. Its storage in hermetically sealed bottles should be insisted upon, and every bottle ought to be tested before use.

Lustig's injectiods.— Lustig and Galcotti have introduced a method of preventive inoculation which