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source of milk supplied to each household was sought, together with details as to how, in what ways, and to what extent it was used by each individual member of the household. The survey served the following purposes :■ — (1) A follow up of visitors to Kaikoura and of residents temporarily absent who might possibly have been infected while there was made possible. Their names and present addresses were obtained and referred to the Sanitary or Health Inspector of the 'district in which they were now residing with a request they be kept under surveillance. Four cases came to notice in this way : two residents, both of whom developed typhoid very shortly after leaving there, and two visitors, both of whom were associated with households having multiple cases. No cases were reported among travellers. This is .-.rather remarkable in view of the hundreds who must have taken meals there during the period of infection. The disinclination of the New Zealand public to use milk as a beverage has probably a definite bearing on this matter. Among those residents of Kaikoura who habitually took raw milk in their tea the attack rate was 4-4 per cent. The risk attached to taking infected milk in one cup of tea is therefore not entirely negligible, even allowing for a slight sterilizing action in cases where the tea is really hot and the amount of milk added small by comparison. Tea-drinkers at the Railway refreshmentrooms could reasonably be expected to run even slighter risk, the common practice being to prepare the tea-milk mixture before the arrival of the train. A few minutes at a temperature approaching boiling-point would be sufficient to render even a heavily infected brew quite harmless. (2) Several sick people were found who had not yet requested medical attention. The names of these persons were given to the local doctor, and in several instances they proved to be early typhoid cases. By this means earlier hospitalization and treatment were obtained than otherwise might have been the case. (3) The opportunity was taken to check up on the general sanitary arrangements, •and steps were taken to have any defects remedied without delay. (4) A reasonably accurate estimate of the population of the township was obtained —its age and sex distribution and the occupation of those gainfully employed. This information could not otherwise have been obtained. The approximate location of each house investigated was marked on a plan. The houses have no street numbers ; in some streets a considerable distance separates adjacent houses and it was therefore not always possible to fix the position of a house -accurately without giving to it more time than the procedure warranted. Although strict accuracy is not claimed for the plan, it nevertheless serves the purpose for which it was intended. It shows the distribution of cases through the township ; their order •of occurrence ; whether one or more cases occurred in any one house ; the source of the milk-supply to each house, whether it was normally boiled or used raw ; and the water-supply reticulation. PART lII.—INVESTIGATION OF THE SOURCE OF THE EPIDEMIC Water-supply As previously noted, all samples taken from the supply prior to the epidemic had proved chemically and bacteriologically satisfactory. At the time of the preliminary investigation on 17th and 18th October the County Engineer was questioned as to recent work done on any portion of the supply system. His information was that the intake had last been inspected on the 20th September, 1947, and prior to that at approximately monthly intervals. The same staff had been employed on this job as for some years past. They were reliable workmen, none of them had had any recent illness, and the possibility of them having infected the supply was considered negligible.

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