Letters 179 



winnowing, lest, as he says, the precepts and dogmata 

 of physic should be disturbed, and the pathology which 

 has for so many years obtained the sanction of all the 

 learned in assigning the causes of disease, be overthrown. 

 He has been playing the part of the advocate, therefore, 

 rather than of the practised anatomist. But, as Aristotle 

 tells us, it is not less absurd to expect demonstrative 

 arguments from the advocate, than it is to look for 

 persuasive arguments from the demonstrator or teacher. 

 For the sake of the old friendship subsisting between 

 us, moreover, and the high praise which he has lavished 

 on the doctrine of the circulation, I cannot find it in 

 my heart so say anything severe of Riolanus. 



I therefore return to you, most learned Slegel, and 

 say, that I wish greatly I had been so full and explicit 

 in what I have said on the subject of anastomosis in 

 my disquisition to Riolanus, as would have left you 

 with no doubts or scruples on the matter. I could 

 wish, also, that you had taken into account not only 

 what I have there denied, but likewise what I have 

 asserted on the transference of the blood from the 

 arteries into the veins ; especially as I there seem to 

 have pointed out some cause both for my inquiry and 

 for my negation, to hint at a certain cause. I confess, 

 I say, nay, I even pointedly assert, that I have never 

 found any visible anastomoses. But this was particularly 

 said against Riolanus, who limited the circulation of 

 the blood to the larger vessels only, with w r hich, there- 

 fore, these anastomoses, if any such there were, must 

 have been made conformable, viz. of ample size, and 

 distinctly visible. Although it be true, therefore, that 

 I totally deny all anastomoses of this description 

 anastomoses in the way the word is commonly under- 

 stood, and as the meaning has come down to us from 

 Galen, viz. a direct conjunction between the orifices of 

 the [visible] arteries and veins I still admit, in the 

 same disquisition, that I have found what is equivalent 

 to this in three places, namely, in the plexus of the 



