42 



present date (12th), this last inoculation has not given any result; but, as 

 only 12 days have elapsed, the case is still within the limits of incubation. !) 



I have to state that the persons mentioned above are the only ones who 

 were inoculated with mosquitoes, in the manner described; and that since 

 June 12th, till now (in the course of seven weeks), barring my first three 

 inoculated men, no other case of confirmed or abortive yellow fever has 

 occurred among the twenty non-immunes whom I have had under 

 observation. 2 ) 



These experiments are certainly favorable to my theory, but I do 

 not wish to exaggerate their value in considering them final, although the 

 accumulation of probabilities in my favor is now very remarkable. I 

 understand but too well that nothing less than an absolutely incontrovertible 

 demonstration will be required before the generality of my colleagues 

 accept a theory so entirely at variance with the ideas which have until now 

 prevailed about yellow-fever. In the mean time, I beg leave to resume m 

 the following conclusions the most essential points which I have endeavored 

 to demonstrate. 



1) This inoculated man D. G. B., came to my office on the 17th of August 

 to be inspected, stating that during the previous six days he had been suffer- 

 ing from headache, loss of appetite and general malaise. On the 24th I found 

 that he had fever (Pulse 100, Temp. 30,1), and he stated that it had been higher 

 on the previous day and also that same morning. The fever however was never se- 

 vere, and the patient did not report himself sick nor took any medicine. The fever 

 ceased, but the pain in the head continued a few days longer. 



Another of my 20 non-immunes was bittern on the 15th of August by a mosqui- 

 to which, 2 days before, had bitten a patient at the Military Hospital, in the 5th 

 day of yellow fever. This inoculated man does not appear to have been sick so far 

 (September 1st). I have not been able to see him since his inoculation, and it is 

 only from hearsay that I have been informed that he has felt poorly on the -lili 

 and 25th of August; but did not report himself sick. 



2) There was a fourth case which was also diagnosed as "abortive 

 yellow fever" at the Military Hospital, but regarding whose diagnosis Dr. Del- 

 gado and I were doubtful. He was one of the 20 nonimmunes of our group, 

 and a different kind of inoculation was tried upon him, the particulars of which 

 will be considered of some interest at the present day. — On the 28th of June 1881, 

 7 a. m., a night-mosquito (C. pungens) was found inside the mosquito-net of a fatal 

 ease of yellow-fever, in the 5th day of attack. Placed in a glass cage, the pun- 

 gens discharged some black blood upon the sides of the tube, the following day. On 

 the 26th of July, a couple of drops of sterilized distilled water were used to di- 

 solve the dry bloody excrement and the same was soaked up with a small bit of 

 sugar, which looked thereafter as if it had been soaked in black coffe. A freshly 

 caugth C. mosquito was now introduced in the phial, and went greedily for the 

 sugar. A little more water was now added, turning the sugar into a reddish brown 

 syrup, from which the same C. mosquito, in the course of % hour had taken a good 

 feed. — On the 29th of July, 2 p. m., L. G. P. one of my 20 non-immunes, was bitten 

 by this C. mosquitos. — On the 31st of July this man was admitted to the Military, 

 Hospital with fever, flushed face, cephalalgia, pain in the back, epigastralgia, in- 

 jected eyes. — On the 3d of August he had neither fever nor albumin. 



