Progress of Foreign Science. 155 



blood in different animals, by the method of Captain Kater. 

 The following is their table of results. 



Real diaDieter 



Name !of the Animal. in parts of an 



English Inch.: 



Grey Mouse . . . -j^Vo 



White Mouse . . . do. 



Sheep 5oV^ 



Horse do. 



Mule do. 



Ox do. 



Chamois .... ^^ 



Stag do. 



She goat .... -^ViJ 



Real diameter 



Name of the Animal. in parts of an 



English Inch. 



Callitriche d' Afr . . -joVo 



Man ^0 



Dog do. 



Rabbit do. 



Pig do. 



Hedgehog .... do. 



Guinea pig .... do. 



Muscardin .... do. 



Ass ...'.. -JTTJ- 



Cat ^-j^ 



According to Sir E. Home and Captain Kater, the mean 

 dimension of the human globule is only -^-j^qj^ of an inch, which 

 agrees perfectly with the determinations obtained by Dr. Wol- 

 laston with his most ingenious micrometer, described in the 

 Philosophical Transactions for 1813. Dr. Young, by the em- 

 ployment of his eriometer, has also furnished various measures 

 which may be depended on. The following are extracted from 

 his Introduction to Medical Literature, published in 1813. 



Diameter of a globule of the blood of the calf ^q'^q of aninch. 



— Human blood diluted with water . . . ^oV?y 



— Humanblood,after being several days in water ■^^X)'S 



— Blood of the mouse irshiy 



— Blood of the thornback TiroT7 



"We thus perceive that the measurements of the foreign 

 observers are, probably, all too high rated. But the most 

 remarkable result which they have arrived at, is that while the 

 globules are circular in all the mammiferas, varying only in 

 size from one animal to another ; that they are elliptical in 

 birds, and vary little in size, the variation being only in the 

 greater axis. They are also elliptical in all animals with cold 

 blood. Another very curious fact is, that the colourless glo- 

 bule which exists in the centre of the particles of blood has 

 exactly the same diameter (y/oo) °f ^^ i'^^^' whatever be the 

 form of the particle and the animal to which it belongs. In 

 conclusion of their memoir we find some interesting remarks 

 on the transfusion of blood. They bled animals to syncope, so 

 that when left alone, or when water or serum of blood at 100° 

 Fahr. was injected into their veins, they died. Into others, 

 exhausted by a similar hsemorrhagy, when they injected the 

 blood of an animal of the same species, every portion of the 

 blood thrown in, re-animated perceptibly this kind of corpse ; 

 and they found, not without astonishment, that after restoring 



