155 



not be sufficiently numerous to warrant absolute conclusions, bul so Ear, 

 every succeeding year has added to their significance. Any impartial critic 

 who is acquainted with the general risk of fatal yellow fever incurred 

 by non-acclimated Europeans during the Eixsl three years of their 

 residence in Havana, would hesitate before attributing to mere 

 coincidences or to a freak of nature the results hitherto obtained by Dr. 

 Delgado and myself with our ".Mosquito inoculations." Since 1881 until 

 the present dale we have thus inoculated 75 non-acclimated individuals 

 whose future course we have been able to Follow during succeeding years, 

 with only two exceptions whom we have lost sight of, having probably left 

 the country. The remaining l'. } , may be thus distributed : 43 have resided in 

 the city during periods between three and seven years after the inoculation ¡ 

 10 have resided between two and three years: 11 between one and two 

 years : 8 between five and twelve months: none of the above 72 having had 

 fatal ydlow fever, and only one of our 70 inoculated subjects having died 

 of that disease, being the loth of our series in. 1884. 



The bacteriological study of yellow fever has not yet demonstrated 

 the true germ of that disease in a manner that will satisfy scientific 

 criticism, but it is a remarkable coincidence Hint contaminated mosquitos 

 introduced into sterilized agar-agar tubes, have been observed to plant 

 upon the surface of the agar jelly which they were seen to prick with the 

 point of their sting, isolated colonies of tie- micrococcus versatilis 

 (Sternberg;, the same micrococcus which ha.s been obtained from culture 

 with yellow fever blister serum procured under strictly aseptic conditions. 



As a practical application of my "Mosquito theory" to a tesl case lei 

 us consider how far that theory will enable us to account for the facts 

 observed in the celebrated yellow fever epidemic thai was carried over 

 from Havana to St. Nazaire and so admirably studied and described by 

 Melier in 1861. In choosing that particular instance I am prompted by 

 my desire of presenting to the American readers the mot interesting and 

 instructive account hitherto given of such an epidemic, and also by my 

 anxiety to refute Dr. Béranger Féraud's objection founded on the supposed 

 imposibility of accounting for the details of the St. Nazaire epidemic by 

 my ".Mosquito theory" (see Béranger Péraud, /." Fievn ■l<i>in<, 1890, p. 



592 . The Amu Marit a wooden Vessel with a crew of sixteen men. sailed 

 from Nantes, France, for Havana where it arrived the 12th of May 1861. 

 During Hie 30 days that tie- vessel remained in Havana note- of the men 

 suffered any sickness beyond malaise, fatigue, loss of appetite or inclination 

 to vomit. She left Havana for St. Nazaire the 13th of June with the same 

 crew. At the start she remained twelve day- be. -allied in the Florida 

 canal, with suffocating heat, frequent squalls and heavy rains. On tie- 

 first day of July two fatal cases of yellow fever mid another not fatal) 



tie- next day declared themselves on board. Two days passed without any 

 new cases and then followed a series of .six new invasions between tin- 4th 



