272 ADDITIONAL NOTES ON CONTAGION. 



seemingly in perfect health, the disease spread rapidly in that ship, so that near one third 

 of ti.e whole crew was more or less affected by it. 



This fact carries a conviction of the reality of infection, as irresistible as volumes of 

 argument ; and it further affords matter of important and instructive information, by 

 proving that the infection may be conveyed by the persons or clothes of men in health. 

 Blane's Diseases of Seamen^y. 605—607. 3d edit. 



The principle which we have endeavoured to illustrate relative to the operation of 

 febrile infection upon individuals unaccustomed to its iufluence has, iu several instances, 

 been strikingly exemplified by circumstances which have occurred in the debtor's prison, 

 and in the bridewell of New- York. The following memorandum, made at my request by 

 Dr. J. W. Francis, is in point on this subject. 



"In the month of September, 1811, a febrile disorder of the typhoid character made 

 its appearance in the debtor's prison of this city : its origin was owing to causes similar 

 to those which usually produce a vitiated state of the atmosphere in confined apartments, 

 the want of pure air, and the crowding of a large number of persons together, &c. &c. The 

 contagion thus engendered was observed to operate with peculiar severity upon those 

 individuals who were suddenly introduced into this vitiated air. About the 16th of July, 

 1814, several cases of the typhus carcerum occurred in the bridewell of New- York. 

 The disease was first observed to exist in an apartment of the institution commonly 

 called the eastern wing, a room about fifty feet long and twenty-five broad. Within a 

 very few days after, the complaint became more general ; and out of eighty -five indivi- 

 duals at that time confined in this part of the building, nearly forty were taken ill with 

 symptoms characteristic of typhoid fever. The disease, in this instance, as in the 

 former, was produced from the local circumstances of the place ; the crowded condition 

 of the ward, the want of cleanliness about the persons and in the clothing of the prisoners, 

 and the neglect of free ventilation. The increased impurities of the atmosphere of the 

 apartment seemed to give additional activity to the virulence of the disease: of the per- 

 sons thus affected a large majority were those who had come from a pure air, and were but 

 recently subjected to the noxious air of the place, several not more than thirty or forty hours, 

 and many not more than three or four days. The infection was more readily communicated 

 to those, too, who were naturally possessed of vigorous and robust constitutions, and its effects 

 were, in most cases, more violent upon persons of this description than upon others. That 

 the sphere of the infection was confined within certain limits, as affirmed by Dr. Lind of 

 the malignant fever at the naval hospital at Haslar, and lately most satisfactorily shown by 

 induction from well-attested facts concerning typhoid infection in general, (see Letter of Dr. 

 Haygarth to Dr. Percival,) was abundantly manifest from the healthy condition of thf 



