ORGANISM OF YELLOW FEVER 255 



Quite as conclusive as the New Orleans experience has been the result of the 

 work on the Isthmus of Panama. This work is also described in some detail 

 among the examples of remedial work. 



THE DEATHS OF REED. CARROLL. AND LAZEAR. 



The deaths of Lazear, Eeed and Carroll, following the brilliant results of their 

 work, are inexpressibly sad. Dr. Lazear was a young man of great ability, 

 admirably trained, whose work, as Dr. Eeed says, was characterized by " a manly 

 and fearless devotion to duty such as I have never seen equaled.^' He " seemed 

 absolutely tireless and quite oblivious of self. Filled with an earnest enthusiasm 

 for the advancement of his profession and for the cause of science, he let no 

 opportunity pass unimproved. Although the evening might find him dis- 

 couraged over the diflficult problem at hand, with the morning's return he again 

 took up the task, full of eagerness and hope." His death was due to accidental 

 inoculation, by an infected mosquito, in the course of his researches at Havana. 

 When the Board resumed its work after his death in ISTovember, 1900, and es- 

 tablished the experiment station at Quemados, they named it in honor of their 

 comrade, Camp Lazear. Dr. Walter Reed, the inspiring genius of the investi- 

 gation, died suddenly November 23, 1902, with his health impaired by his 

 strenuous labors. He had reaped some of the honors following his monumental 

 work, but by no means all. His name will live as that of one of the great bene- 

 factors of the human race. Dr. Carroll, although he lived for a few years longer, 

 died September 16, 1907. At Havana, in 1900, he suffered the first experi- 

 mentally produced attack of yellow fever and it proved a severe one. His early 

 death was undoubtedly due to the effect of the disease. He lived just long 

 enough to see the substantial results which followed the great work with which he 

 had been so prominently connected. Personally, all three were of the highest 

 type, and each is mourned by a host of warm friends, as well as by the world 

 at large. 



THE SEARCH FOR THE CAUSATIVE ORGANISM. 



The experiments just recorded demonstrate beyond all doubt that the specific 

 agent of yellow fever inhabits the blood. A most prolonged microscopic search 

 was made, not only by Eeed and Carroll, but by many other investigators, with 

 fresh and stained preparations of blood, taken at various stages of the disease 

 and during early convalescence. But all of this search was negative. Further 

 search was made in the bodies of infected mosquitoes dissected fresh, and also by 

 means of serial sections of the hardened insect, and no results worthy of men- 

 tion were obtained. The attention of Eeed and Carroll was soon called by Welch 

 to the important observations of Loeffler and Frosch on the etiology of the foot- 

 and-mouth disease of cattle. In this disease the lymph, collected from the blebs 

 present in the mouth and feet of sick cattle, had been diluted and passed several 

 times through a porcelain filter, with the result that this strained and diluted 

 Ijrmph injected into calves produced the disease as promptly as with others that 

 had been injected with the same quantity of unfiltered lymph. The German 

 authors decided that there were two possible explanations of this result : either 



