4-22 Ur. Spurgiii's Outlines of' a Philosophical 



amitied a small portion of human blood on a glass plate, to 

 ascertain the real shape and size of the globules. I then found 

 in one square of the micrometer (which was the 160,000dth 

 part of a square inch) two of these globules, which wei'e se- 

 parated to a considerable distance from the rest; they were 

 entirely disengaged from the colouring substance, and lay in 

 pure clear serum, which covered the surface of the whole square 

 inch of the micrometer. Having placed this particular square 

 immediately under the focus of the microscope, I attentively 

 examined the globules for about six or eight minutes, when I 

 perceived two extremely minute opaque spots arising in the 

 clear serum within the same square of the micrometer, and 

 which seemed increasing in size. In a few minutes more I 

 perceived five or six more such opaque spots arising and gra- 

 dually increasing, and assuming the same form and apj^ear- 

 ance as the two original globules; but the moisture of the 

 serum being nearly evaporated, I diluted it with water, when 

 all the seven new globules, as well as the two original ones, 

 floated in the water, and appeared of pi'ecisely the same shape 

 and white colour; and three of the new globules were of the 

 same size as the original ones, but the rest were smaller. 

 When left on the glass to dry, the globules remained of the 

 same shape and size as they were whilst floating in the serum. 



" The above experiment," he proceeds to say, " I have 

 repeated a great many times with human blood, as well as 

 with sheep's and calves' blood ; and the results have been al- 

 ways the same. When warm and fresh blood was used, the 

 serum covering the surface of a 160,0U0dth part of a square 

 inch, produced from 6 to 12 globules; but when the scrum 

 was diluted with water, the number of globules produced was 

 less, and they were smaller in size. 



" On the 11th of August 1817, I poured half a pint of warm 

 sheep's blood into a glass vessel, and left it 48 hours at rest to 

 coagulate. I then poured off the serum into another vessel, in 

 which it remained at rest six hours; with this serum a glass 

 tube four inches long, and 3-8ths in diameter inside, was filled 

 to overflowing, and closed with a good cork, and covered with 

 a bladder. The serum was as clear as water; and although I 

 examined it very attentively, I could not see more than 15 or 

 20 globules in tlic whole extent of the tube. It was kept in- 

 verted in a glass of water. At the end of seven days, upon 

 holding the tube between my fingers, which were tolerably 

 warm, and examining it with a double lens of considerable 

 magnifying power, I saw some hundreds of globules rise from 

 the bottom and ascend in a straight line in the centre of the 

 tube, and when arrived within about half an inch of the up- 

 per 



