THE BLOOD. 63 



the largeness of the surface, to have coagulated in much less 

 time; but just the contrary happened; for the blood in the 

 cups was first completely coagulated, that in the saucers next, 

 and that on the plates latest of all. But, as the experiment 

 seems curious, it may be proper to give a more particular detail 

 of what was observed. 



On looking at the first plate, at the end of seven minutes 

 after it was set down on the window, the surface of the blood 

 in the cup was considerably transparent, and a pellicle (that is 

 the surface beginning to coagulate) was formed upon it ; but 

 no transparency was distinguishable on that in the saucer, nor 

 could any pellicle be observed upon drawing a pin through it, 

 or through that which had dropped upon the plate. At the 

 end of fifteen minutes the blood in the cup and in the saucer 

 was pretty much coagulated, or had a thick pellicle, whilst none 

 could yet be observed on that upon the plate. At the end of 

 fifty -five minutes that in the cup was just beginning to part 

 with its serum, whilst the blood in the saucer was not yet com- 

 pletely coagulated; for on inclining it to one side, apart of the 

 blood appeared fluid under the pellicle. That on the plate was 

 now coagulated. They were all three sizy ; and the blood in 

 the saucer had a size which seemed to be as firm and in as large 

 a quantity nearly as that in the cup ; and the size upon the blood 

 in the plate was thick enough to be easily distinguished. 



In the second plate, at the end of seven minutes after being 

 set on the window, both the blood in the cup and in the saucer 

 was beginning to coagulate ; and had a pellicle of a considerable 

 thickness, and were both sizy ; but no pellicle appeared on any 

 of the three portions that had dropped on the plate. At the 

 end of fifteen minutes, that in the cup was firmly jellied, that 

 in the saucer not quite so much, and one of the spots on the 

 plate was but just beginning to coagulate at its edge. At the 

 end of twenty-five minutes, the two last spots were still per- 

 fectly fluid, but in twenty-eight minutes they were beginning 

 to coagulate ; whilst the blood in the cup was now parting with 

 its serum. At the end of fifty minutes a considerable quantity 

 of serum had separated in the cup, and the separation was just 

 beginning in the saucer. 



This experiment was repeated on another person's blood two 

 days after, in the presence of Mr. Field and Mr. Hendy, two 



