THE PRODROMUS 223 



P- 22. particular place, thereupon to be added to the solid parts, just 

 as the particles worn from the solid parts flow back into the 

 same cavities, to be restored to the blood again in order that 

 with its help they may be carried back to the external fluid. 

 The doctrine concerning the fluid of these cavities agrees in 

 many ways with the teaching of the great Hippocrates ^ concern- 

 ing air. 



Although I may not be able to determine why different fluids 

 are secreted in different places from the same blood, I hope, 

 nevertheless, that a few things hold true for determining that 

 • question ; since it is certain that such secretion does not depend 

 upon the blood, but upon the places themselves. An examina- 

 tion of this matter is comprised under these three heads : 



1. The consideration of the capillary veins of the internal 

 common fluid ; with which alone they concern themselves who 

 attribute all things to cribration through the different pores — 

 with whom I, too, was for a long time numbered. 



2. The consideration of the internal peculiar fluid, with which 

 alone they busy themselves who ascribe a special ferment to 

 each part. Their belief may be partially true, although the 

 name ferment rests upon a comparison taken ^ from too specific 

 a process. 



3. The consideration of the particular parts of a solid ; and 

 upon this they especially lay emphasis who acknowledge, by 

 ascribing to each part its own form, that they recognize in it 

 something peculiar to that part, but which is unknown to us, 

 and which, according to the knowledge of matter which we have 

 so far gained, can be nothing else than the porous surface of 



P. 23. that solid, and the attenuated fluid permeating the pores. 



I should wander too far afield if I were to apply the foregoing 

 statements to the explanation of those things which take place 

 in our body every day, and still they cannot otherwise be ex- 

 plained. It will suffice to have hinted here that the particles 

 which separate from the external fluid in various ways are 

 carried into the internal common fluid through the intervening 



iThe Ilepi ^aStv of Hippocrates assigns air in the body as the cause of all diseases, and 

 different diseases as merely due to different organs thus affected ; cf. the edition of Hippoc- 

 rates by Littrd, Vol. VI, pp. 92, 104-106, and Maar, op. cit.. Vol. II, p. 335. 



^For desumpta in the Florentine edition of 1669 read desumptae. 



