222 NICOLAUS STENO 



of canals without intermediate capillary veins, that is, without 

 p. 21. cribration ; and the result is that although the cavities contain- 

 ing the fluids mentioned may be closed at times, still whenever 

 they are opened, they discharge all their retained fluid without 

 a dividing membrane. 



I call that fluid internal which does not communicate with the 

 external fluid except through the intermediate strainers of the 

 capillary veins, and therefore never discharges all its contents 

 naturally into the external fluid without a dividing membrane. 



The internal common fluid is that which is contained in the 

 veins, arteries, and lymphatic ducts, at least in those ducts which 

 connect the conglobate glands^ and the veins. I call this fluid 

 common because it is distributed over all parts of the body. 

 Concerning another common fluid which resides in the nerve 

 substance, I have nothing to say, because it is unknown. 



The internal peculiar fluid is that fluid which is sent about in 

 the capillary veins of the common fluid, and which varies with 

 the diversity of places ; for it is one thing in bloody parenchy- 

 mata,^ another in bloodless parenchymata, another around the 

 muscle fibres.^ another in the capsule of the ovum, another in 

 the substance of the uterus, and still another in other places. 

 For that belief accords with neither reason nor experience, which 

 supposes that the ends of the veins and arteries terminate in the 

 smallest possible particle of the body for the distribution of 

 warmth and nourishment at that point.* But there are cavities 

 everywhere, and the elements which have been secreted into 

 these cavities from the blood are mingled with the fluid of that 



1 The lymphatic glands, as shown by Steno's treatise De Glandulis Oris et Novis inde 

 Prodeuntibus Salivae Vasis, printed by Maar (Vol. I, p. 20, and note, p. 227). 



2 The name parenchyma was given by Erasistratus to the peculiar substance of the lungs, 

 liver, kidneys, and spleen, on the theory that this substance, as distinguished from the flesh of 

 the muscles, was formed from the blood which flowed from the veins and coagulated in the 

 organs mentioned. See Galen, Ilepi t^5 rwv ^apf/.a.Kuiv Kpao-eios koI Avva/Acws, book XI, 

 prooemium ; and eis to Trepl (j>vcreo>s avOpwirov ^lJSXlov 'liriroKpoLTovs '^Trojxvriixa TrpSiTov, 4 

 (edition of Mewaldt, Helmreich, and Westenberger, Leipzig, 1914, p. 6). 



^ Steno's phrase is circa fibras matrices. This is defined in Elementorum Myologiae Speci- 

 men, Maar, op. cit., Vol. II, p. 69: 'The fibra matrix is a certain bundle of very minute 

 fibrillae closely joined longitudinally. ... I call such a fibre motfix because it seems to me 

 to be the true organ of motion in an animal. For the muscle is nothing except a collection 

 of such fibres.' 



^ Steno refers to the theory commonly accepted before Harvey's demonstration of the circu- 

 lation of the blood. This is the view' expounded in Plato's Timaeus (79, So), a work which, 

 in a crude Latin translation, profoundly influenced the science of the Middle Ages. 



