1895.] MICROSCOPICAL JOURNAL. 313 



taiuing a single layer of blood with the corpuscles even- 

 ly distributed. When quite dry I pour over the prepara- 

 tion a strong solution of iodine, and remove after about a 

 minute. It will dry rapidly, and then be ready for 

 microscopical examination. 



I may here state that preparations of blood treated in 

 this manner will remain in good form for an almost in- 

 definite length of time, needing no glass cover or any 

 preservative, and can be examined dry. 



This examination of preparations of blood, dry, and 

 without the addition of a glass cover, I consider an im- 

 portant feature of my work, and accounts for my seeing 

 so much which had escaped previous observation, because 

 I noticed that the addition of Canada balsam and other 

 preservatives and a cover, caused most of the special 

 features to disappear. 



I was surprised to find on making a microscopical ex- 

 amination of human blood thus prepared, that all the 

 red corpuscles in the field showed in each instance a 

 clearly defined nucleus, some in the centre of the cell, 

 and at the edge in others; in many instances two nuclei 

 were visible in the one cell, and in rare instances they 

 were in a cluster of five or six. In some instances were 

 exhibited what a Gferman authority calls homogeneous 

 cells, having merely a very fine line as an outer ring, 

 and in some cases such cells contained a nucleus. 



At the time I made a very fine photograph of this 

 slide showing all these appearances above described in 

 the most clear and definite manner, but I failed to find 

 any lepecialist who would take the slightest interest in 

 the subject. I was aware that D,r. Osier, late of Canada, 

 and then holding a professorship at the Johns Hopkins 

 University, had given much attention to the microscopi- 

 cal appearance of blood, and I forwarded to him copies 

 of my original photograph and enlarged copies of the 

 same; but he came to the conclusion that because they 



