xxviii INTRODUCTION. 



to a change in the red corpuscles ; and Bordenave 1 had a similar 

 opinion. These doctrines foreshadow either those of SirE. Home, 

 or of Mr. Jones and Dr. Simon, mentioned at pages xxxi and xli 

 of this Introduction, and in the Notes i, xvm, and cxviu. 



Ruysch 2 obtained the fibrous matter from the blood-clot by 

 washing, and from fluid blood by agitating it with a twig. He 

 described the resemblance of the fibres to a true fibrous mem- 

 brane, and depicted the pseudo-membrane, as he terms it, pro- 

 cured from his own blood and from that of a pig, on the branch 

 of an African plant. The ' Ruyschian membrane ' is often men- 

 tioned by succeeding writers. 



At this time, then, the spontaneously coagulable matter of 

 the blood had been well understood ; while the fibrous structure 

 of fibrin was thoroughly described, and often with the aid of 

 the microscope. But the elementary molecules, and the cells 

 or organic germs in the fibrin were overlooked; for although 

 Leeuwenhoek 3 probably saw either some of these or the pale 

 floating globules of the blood, 4 his description is obscured by 

 hypothetical errors. The same objection occurs with regard to 

 the observations made upwards of a century afterwards by Sir 

 Everard Home and Mr. Bauer, 5 though they described and even 

 accurately measured the pale globules both of the buffy coat of 

 the blood and of the coagulated lymph in inflamed parts ; and 

 yet, to suit a preconceived hypothesis, concluded with the error 

 that these globules are smaller than the red corpuscles. 



In Britain, Keill, 6 Jurin, 7 Thomas Morgan, 8 John Cook, 9 

 Arbuthnot, 10 William Cowper, 11 Martine, 12 and Langrish, 13 



1 Essai sur la Physiologic, torn, i, p. 155, 8vo, 4eme edit. Paris, 1787. 



2 Thesaurus Anat. Sept. No. xxxix, tom.ii, p. 19, tab. iii, fig. 6, 4to, Amstelaedami, 

 1707. 



3 Philosophical Transactions, 1675, vol. x, p. 380. 



4 For the observations of Senac and Hewson on this point, see Note CXLVI, p. 282. 



5 Philosophical Transactions, 1820, pp. 3-5. 



6 Essays on several parts of the Animal (Economy, p. 96, 2dedit. 8vo, Lond. 1717. 



7 Philosophical Transactions, 1719, vol. xxx, p. 1000. 



8 Philosophical Principles of Medicine, pp. 108, 110, 177, 251, 2d edit. 8vo, 

 London, 1730. 



9 Essay on the Whole Animal GEconomy, vol. ii, pp. 18, 19, 8vo, London, 1730. 



10 Essay concerning Aliments, pp. 121, 163, 8vo, London, 1731. 



11 Anatomy of Humane Bodies, tab. 23, fig. 16, fol. Leyden, 1737. 



12 Medical Essays and Observations, vol. ii, pp. 77, 86, 8vo, Edinburgh, 1747. 



13 Theory and Practice of Physic, pp. 66-7, 8vo, London, 1735. 



