July 10, 1885.] 



SCIENCE. 



27 



home, or imported, the testimony is uni- 

 form that epidemics of yellow-fever have their 

 starting-points in the lowest, filthiest quarters 

 of seaport towns, than which nothing can be 

 filthier or more disgusting. It can hardly be 

 necessary to dwell upon this point. With the 

 improvement in the water-side precincts of 

 New York, Philadelphia, and other North- 

 Atlantic seaports, 3'ellow-fever has ceased to 

 be the devastating pestilence which it was in 

 the daj's of Benjamin Rush. In those days the 

 purlieus of such cities were little better than 

 the}^ now are in the towns and cities of the 

 Spanish main, where it still rages. In the lat- 

 ter, it is true, there is alwa3^s present the added 

 factor of a favoring condition of temperature ; 

 and, less constantly, this also affects our Gulf 

 and South-Atlantic seaports. But this of 

 itself should be an additional incentive to se- 

 curing the best attainable sanitary condition. 

 Foul drains, filthy streets, reeking gutters, 

 neglected cloacae, excremental accumulations, 

 decomposing garbage, rotting fruit and vegeta- 

 bles, the drainage of sugar and molasses casks, 

 — the wonder to the sanitarian, as he views 

 such scenes for the first time under the tropi- 

 cal raj's of a summer sun, is not that j^ellow- 

 fever occasionally occurs, but that pestilence 

 in some form is not always present. In the 

 endemic home of 3'ellow-fever, ' sanitation ' is 

 an unknown term ; and, in the degree that its 

 import is ignored along our Gulf and South- 

 Atlantic coasts, the disease finds favorable 

 conditions for establishing itself whenever its 

 poison is introduced. 



An obvious precaution is suggested by the 

 fourth proposition, — that yellow-fever is a dis- 

 ease of cities and crowded populations.^ As a 

 rule, it is limited not only to cities, but to 

 sharply defined quarters of cities. The great 

 specific gravit}' of the poison, and its property 

 of clinging to surfaces, are shown *in this limi- 

 tation of extension. Frequently its rate of 

 progress may be mathematically defined, so 

 many feet per day, independent of any recog- 

 nized influence, except a perpendicular obsta- 

 cle. A board fence has been known to stop 

 its progress, as in Mobile ; or a blufl^* bank to 

 hold it at bay for weeks, as in Memphis. Not 

 only do the higher portions of a city suff'er less 

 than the lower, other things being equal, but 

 the upper stories of individual houses are safer 

 than the lower. Yellow-fever is essentially a 

 local disease, its existence depending upon par- 



1 Its occasional extension to small places, and even to planta- 

 tions and isolated houses, does not affect the general accuracy 

 of this proposition. Such extension occurs only during wide- 

 gpread and virulent epidemics, when, it may he inferred, the 

 specific poison ij generated in such quantity and intensity as to 

 be the more reaidily transplanted from place to place. 



ticular circumstances of place : hence, when 

 the disease manifests itself in a localit}', the 

 imperative duty of the sanitary authorit}^ is to 

 remove from the infected place (be it house, 

 street, ward, or quarter) all those susceptible 

 to it, — to depopulate the infected district, if 

 it tends to become epidemic, by removal to 

 camp, if only a few miles distant, as was done 

 with such satisfactory results in Memphis dur- 

 ing the epidemics of 1878 and 1879, and re- 

 peatedly before that time in the U. S. army. 

 The cordon sanitaire may be employed to pre- 

 vent people from going into an infected dis- 

 trict ; but with the present resources of sanitary 

 science, and definite knowledge of this disease, 

 its use to prevent escape from such a district 

 is a barbarism of the same character as the 

 old-time quarantine of detention. 



In a word, the precautions to be taken 

 against yellow-fever are the same as those 

 which common sense and experience have 

 shown to be adequate against the other exotic 

 infective diseases : to wit, a thorough system 

 of sanitary supervision and control of inter- 

 course, both by sea and land, for the exclusion 

 of the specific poison ; and, supplementing 

 possible (if not inevitable) defects in this, the 

 destruction of the conditions necessary to the 

 life and activity of the poison by general and 

 local sanitary effort within our own territory. 



F. W. Reillt. 



CHICAGO-RIVER POLLUTION. 



It is worthy of note that the first sanitary 

 regulation made by the authorities of the town 

 of Chicago had reference to the protection of 

 the river from pollution. Nov. 7, 1833, the 

 town trustees declared it to be unlawful " to 

 throw or put into the Chicago River, within the 

 limits of the town, any dead animal or animals, 

 under a penalty of three dollars for every of- 

 fence." More than half a century later, the 

 problem of establishing and maintaining an 

 inoffensive condition of this stream still de- 

 mands the attention of the sanitarian. A 

 glance at the topography of the region will 

 facilitate comprehension of the problem, and 

 assist in its solution. 



While the western portion of Cook county 

 is embraced in the general slope of the water- 

 shed of Illinois and the interior system of 

 drainage of the State, — which is to the south 

 and west, and ultimately into the Gulf of 

 Mexico, through the Mississippi River, — the 

 region of Chicago, embracing the greater por- 

 tion of Cook county, drains naturally into the 

 Gulf of St. Lawrence, through the Great Lakes 



