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A simple technique for the location of enteric carriers in towns by means of serial sewage examinations has been described in two earlier papers by Moore (1948Moore ( , 1950. The principle underlying this method is essentially that some form of continuous sampling of the sewage passing along a particular sewer should be a more sensitive index of the passage of enteric organisms than the examination of bulk samples of sewage, taken from the sewer at times which could not be related in advance to the personal habits of a hypothetical excreter of enteric organisms proximal to the point of sampling. It was found that a gauze swab immersed in the flowing sewage for 48 hr. was an effective trap for enteric organisms and that, when suitable cultural techniques were used, this method gave consistently good results and was moreover far easier in practice than the awkward procedure of collecting sewage in bulk from various points on a sewerage system. It was also shown that when enteric organisms had been isolated from a swab, it was possible to trace the organism back to an individual household by systematic sampling from key manholes on the sewerage system in the area concerned.In both of the papers cited, reference was made to investigations carried out at Sidmouth during the past few years. This work was undertaken mainly to develop methods for the location of enteric carriers, and the techniques which proved satisfactory in Sidmouth were then successfully applied to the solution of an unexplained paratyphoid outbreak at another place. Our investigations were also relevant to local problems, however, as many sporadic cases of both typhoid and paratyphoid fever have been notified from Sidmouth during the past 15 years and its record in this respect has been far worse than that of any other town of similar size along the South Devon coast. It was hoped that our investigations might throw some light on these infections, the majority of which had not been satisfactorily explained by the usual methods of epidemiological inquiry. Unfortunately, a long enforced leave of absence of one of us has curtailed the scope of the investigations originally planned, and the survey of Sidmouth has in consequence not been completed to our satisfaction. Such results as we have obtained are here presented, and various problems posed by the survey are discussed. Some suggestions are also made on the possible application of the methods we have used to various epidemiological problems.

A series of infections with Salmonella paratyphi B which occurred at a seaside resort in North Devon every summer between 1943 and 1946 concentrated local attention on a very unsatisfactory sewage outfall, which discharged into the sea at all stages of the tide and frequently caused fouling of the adjacent beach. The local authority, concerned at the possible association between beach pollution and the enteric infections and also by the prospect of serious economic loss in an area dependent on the summer tourist traffic, planned a new sewage disposal scheme based on the controlled discharge of sewage into the sea from a point which had been shown by float tests to be more suitable than the old outfall site.After discussion with the local sanitary authority and the consulting engineers who drew up the plans for the new scheme, it was agreed that bacteriological surveys of the outfall area should be made both before and after the installation of the new scheme. The main purpose of this paper is to give the results of these surveys, the first of which was carried out in the summer of 1948 and the second in the summer of 1950, 3 months after the new scheme had come into operation. ENGINEERING AND EPIDEMIOLOGICAL ASPECTS OF BEACH POLLUTIONThe problem of sewage pollution of bathing beaches is a complex one. The discharge of sewage into the sea from coastal towns is determined partly by financial considerations and partly by the lack of suitable space for sewage works in most seaside resorts. If the sewage outfall can be pushed far enough out to sea and the sewage liberated at a reasonable depth below the surface, pollution of beaches will not occur, and this method has been successfully used at several seaside towns in this country, e.g. Bournemouth and Brighton. The prolongation of outfalls for long distances under the sea is, however, both difficult and expensive, and in many coastal areas sewer outfalls discharge sewage just below or even above low-water mark. Where this occurs on a beach used for bathing, two quite distinct problems arise. One is the health hazard occasioned by the deliberate discharge of potentially pathogenic material; the other is an aesthetic problem when the amenities of the area are affected by deposition of excreta on the sands, discoloration of the sea water by 'sleek' fields and the formation of slimy deposits on the beach round the outfall. The disfiguration of a popular beach by sewage may discourage summer visitors, and active local authorities are justified even on economic grounds in planning sewage disposal schemes which minimize the pollution of their beaches.If this problem is approached on frankly aesthetic grounds, it should be possible to set a maximum permitted level of sea water contamination on a bathing beach below which a sewage nuisance is very unlikely, and plans for an adequate sewage

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