November 21, 1907] 



NA rURE 



69 



l.eighton, is of much wider interest, containing tlie par- 

 ticulars of a most searcliing investigation as to what 

 distance it is possible for the typhoid bacillus to travel in 

 a running' stream, and so convey disease from one place 

 tu another. 



It is well known that the city of Chicago, in order to 

 preserve the purity of the water in Lake Michigan, from 

 which it derives its water supply, diverted the sewage 

 from the lake into a canal thirty miles long for convey- 

 ing it into the Desplaines river, which connects with the 

 Illinois River, and so with the Mississippi, on which is 

 situated the town of St. Louis. The law authorising- the 

 construction of the canal required that the sewage was to 

 be diluted with 20,000 cubic feet of water from the lake 

 per minute for each 1000 inhabitants of the sanitary 

 district. 



.-\n epidemic of typhoid fever having broken out in St. 

 Louis, the sanitary authorities were advised that this 

 could be traced to germs transported from Chicago, where 

 a large number of typhoid-fever cases had prevailed. 

 The State of Missouri, in which St. Louis is situated, 

 therefore commenced proceedings in the Law Courts 

 against the State of Illinois and the sanitary district of 

 Chicago for an injunction to prevent further pollution of 

 the Mississippi water. The evidence taken " comprises 

 the best symposium on river pollution, its biological and 

 chemical aspects, and general and special sanitary signifi- 

 cance that has ever been assembled." The contentions 

 of both parties were supported by all the most qualified 

 chemists, biologists, and sanitary experts in the United 

 States, no less than forty-one expert witnesses having 

 been called. The record of the evidence occupies 8000 

 printed pages. The paper now under notice contains a 

 digest of this evidence and the finding of the court. 



The distance between the two cities is 322 miles, and 

 there are on the main stream and its tributaries between 

 these two points a population of ij million inhabitants. 

 The quantity of sewage discharged from Chicago at the 

 time of the trial was given as 1500 tons daily, and the 

 volume of fresh water sent down with this 300,000 cubic 

 feet a minute. By means of float experiments, most 

 carefully carried out, it was shown that it took nearly 

 eleven days for the water to travel from Chicago to St. 

 Louis. 



It was also shown that typhoid fever had prevailed 

 more or less every year for the previous ten years in the 

 towns on the banks of the Mississippi and its tributaries, 

 the number of cases in iqo2 amounting to more than 

 1200, of which 800 occurred in the Chicago district. 



One of the most interesting of the experiments made 

 to determine how long a typhoid bacillus would live in a 

 running stream was the discharge into the Mississippi 

 River, just below the junction with the Illinois, of several 

 millions of HaciMus prodigiosus, an organism of the same 

 type as the typhoid bacillus, but which had never been 

 found in the Mississippi water. This bacterium was 

 subsequently found in samples collected at different places 

 between the Illinois outfall and the intake of the St. 

 Louis water supply. It was shown that this particular 

 bacillus could live in running water for periods extending 

 from thirty to fifty days, and was still alive when the 

 experiments ceased. Dr. Ravold, who conducted these 

 experiments, testified that it was highly probable that a 

 typhoid bacillus can be carried in a virulent condition a 

 distance equal to that between Chicago and St. Louis. 

 It was admitted that sunlight was detrimental to the 

 life of "bacteria," but the effect depends on the turbiditv 

 of the running water and the depth to which it will 

 admit the sun's rays. In the Illinois River the effect of 

 the sun was dissipated in a depth of less than a foot. 

 The factors which cause the disappearance of bacteria are 

 ner.ntion, dilution, sunlight, sedimentation, and absence of 

 fiiod supply. 



Cases were brought forward in which it was shown 

 that tvphoid fever germs had travelled along a river 

 upwards of fiftv-seven miles, and caused infection in 

 water supplies ; in another outbreak of tvohoid which had 

 been investigated, the distance over which the typhoid 

 germ had been traced as having travelled was 17? miles, 

 and in another 113 miles. It was shown that although 

 the dilution of the Chicago sewage by the clean water 



NO. Tg86, VOL. yy] 



from the lake would render it less injurious, yet this 

 would not destroy the typhoid bacillus or hinder it from 

 travelling down the river. 



On the other side it was contended that it had never 

 yet been satisfactorily proved how long the typhoid 

 bacillus will live in tlie sewage-contaminated water of a 

 stream, but, according to laboratory experiments, the 

 time might be stated as varying between weeks and 

 months. It was held by some experts that typhoid bacilli 

 disappeared when water bacteria became active. As an 

 illustration of this was quoted the fact that the water 

 of the river Spree, which passed through Berlin and 

 received the city sewage, after the course of a few miles 

 widens out into a quiescent body of water. The sewage 

 water entering the lake became so purified that when 

 leaving it was practically as pure as it was above Berlin 

 before it became polluted. The same result happened to 

 the river Limtnat, which flows into Lake Zurich. 



It was stated also that the river Seine, after receiving 

 the sewage of Paris, purified itself within a distance of 

 forty-three miles. 



.'\n elaborate series of experiments was made to deter- 

 mine the longevity of the typhoid bacillus under natural 

 conditions in the water of the drainage canal and other 

 places. The bacilli were placed in parchment sacks 

 suspended in the water by floats, through which sub- 

 stances in solution could pass, but which did not permit 

 the bacilli to pass out. These sacks were suspended in 

 a light cage, and into them was introduced a quantity 

 of sewage, together with a strong culture of typhoid 

 bacilli. The results of these experiments, closely simu- 

 lating those' in nature, indicated that the typhoid bacillus 

 does not survive for a period longer than four days in 

 water similar to that discharged from Chicago. 



Experiments made by the witnesses for Chicago as to 

 the survival of the B. prodigiosus failed to confirm those 

 of the complainants, and their evidence was to the effect 

 that it was improbable that the organisms reported to 

 have been found at the intake of the St. Louis water 

 were the same as those placed in the drainage canal. It 

 was also stated that, although the typhoid bacillus may 

 remain alive in the human body for many months, and 

 in wet soil some weeks and possibly months, yet in water 

 it dies out quickly, the length of time depending on the 

 character of the water, being longer in pure water than 

 in that which is polluted, where it has to fight for its 

 existence with other bacteria. 



The judgment of the Supreme Court of the United 

 States was given in February, 1006, to the following 

 elTect : — that the case as presented to the court fell so 

 far below the allegations that it was not brought within 

 the princioles heretofore established, and the Bill was 

 therefore dismissed. 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE. 



Cambridge. — The thanks of the University are to be 

 given to the Rev. Dr. Bonney, who has presented to the 

 Sedgwick Museum the whole of his collection of rock 

 slices, consisting of two thousand seven hundred specimens, 

 of which the British examples number about thirteen 

 hundred. The latter represent especially the rocks of 

 Cornwall, Charnwood, the Wrekin, the Hunter pebbles, 

 north Wales, Scotland, and the Channel Islands. The 

 European collection contains some four hundred and fifty 

 specimens collected from different parts of the Alps, 

 Brittany, and the .Ardennes. There is also a large collec- 

 tion of specimens from the Himalayas, Novaia Zemlya, 

 .Ararat, Canada (Eozoon, &c.). Rocky Mountains, .Andes, 

 Ecuador, Bolivia, Aconcagua district, Socotra, and the 

 diamantiferous district of South .Africa. 



Dr. Myers has been appointed university lecturer in 

 experimental psychology until Michaelmas, 1912, and Dr. 

 W. H. R. Rivers university lecturer in the physiology of 

 the senses until the same date. 



Mr. A. Hutchinson has been appointed chairman of the 

 examiners for the natural sciences tripos. 



The Walsingham medal for 1007 has been awarded to 

 E. Mellanbv. formerly research student at Emmanuel 

 College, for his essay on the metabolism of creatinin and 



