74 SCIENCE PROGRESS 



the blood-platelets were seen and described by Riess, Kolliker, 

 Birch-Hirschfeld, and Osier. To this period also belongs the 

 work of Zimmermann and the unconfirmed observations of 

 Lostorfer. The "elementary particles" described in i860 by 

 Zimmermann 1 were seen in the supernatant liquid which collected 

 above a sediment obtained by allowing blood to flow from a cut 

 vessel into a solution of neutral salt. As far as it is possible to 

 form an opinion from his description of the aspect and size 

 of the particles, it is probable that many, if not all, of these 

 were undoubted blood-platelets. 



Osier's paper was published in 1874, but in the preceding 

 year a short account by Osier and Schafer, entitled " Uber einige 

 im Blute vorhandene Bacterien-bildende Massen," had appeared 

 in the Centralblatt filr die medicinischen Wissenschaften. It is 

 this paper which is generally quoted by recent Continental 

 observers. More than thirty years have elapsed since Osier's 

 observations were made in the Physiological Laboratory of 

 University College, and the unfortunate title to his paper, " An 

 Account of Certain Organisms occurring in the Liquor San- 

 guinis," is probably responsible for its neglect. The bodies he 

 described so fully and accurately are undoubtedly blood-platelets, 

 and some of his figures appear to-day in the text-books. When 

 we remember how uncertain and inconclusive was our know- 

 ledge of bacteria, the ignorance as to whether these occurred in 

 the normal fluids and organs of the body, and call to mind that 

 Koch's work on Wundinfectionskrankheiten did not appear until 

 1878, it is easy to understand that Osier considered the motile 

 transformations of the platelets were minute organisms within 

 the blood and blood-vessels. In the blood of rodents, and 

 particularly well in that of the rat, when the blood was mixed 

 with serum and examined continuously for one to four or five 

 hours, the formed bodies or platelets were noticed to alter. They 

 developed processes, and the " developed forms " resembled 

 spermatozoon-like forms, some of which possessed two or three 

 tails and moved freely among the corpuscles. Osier's figures 

 leave no doubt but that these transformations are exactly similar 

 to what we have observed to occur when human blood mixed 

 with oxalates is examined for the same length of time. They 

 •are particularly well seen in human blood, and also in that of 

 other mammals, while the admixture of oxalates with the blood 



1 "Zur Blutkorperchenfrage," Virch. Archiv, xviii. i860. 



