XIV LIFE AND WORKS OF NICOLAUS STENO 



maxillary gland, and from one of the same kind near the tonsils. 

 Leading from this glandula communis was a fourth vessel, which to* 

 gether with the other lymphatic vessels of the head opened into the 

 vena cava at the place, where the jugular and axillary veins joined. 

 This discovery was particularly interesting, because it showed that 

 the lymph was conveyed from and not to the salivary glands, which 

 was entirely at variance with the theory maintained by Bils and other 

 of Steno's contemporaries, viz. that all the watery secretions and humors 

 came from the thoracic duct. By this discovery Steno was involved 

 in a controversy, not with Bils himself, but with Deusing, according to 

 whom there were also other ways, in which the saliva could be se* 

 creted, e.g., during excessive salivation, by the direct flowing down of 

 the watery fluid of the brain into the cavity of the mouth through the 

 apertures in the sphenoid bone. In his Dissertation Steno on the con? 

 trary maintained that the arterial blood must be supposed to be of 

 such a composition, as to be able to provide materials for the saliva, 

 which, through the influence of the nerves, is secreted by the glands, 

 by means of a process, which might be conceived as a temporary con* 

 striction of the minute blood-vessels, in which manner a mechanical 

 hindrance was made for the passage of the blood, which would then 

 give off its more watery elements. — Against Everaerts who, as related 

 above, likewise agreed with Bils in his view of the function of the 

 lymph, being of the opinion that the lymph was conveyed direct to 

 the mammae, to be there secreted as milk, Steno strongly asserted that 

 the mammae were glands, and that they secreted milk in a manner 

 analogous to that in which the salivary glands secreted the saliva. 



Steno's next researches concerning glands turned upon the lachry* 

 mal glands. Even Wharton thought that the tears originated in the brain, 

 from where they passed through the nerves, and that their flowing 

 was due to a contraction of the brain, which occasioned the tears 

 to be squeezed out, the tears subsequently passing through the nerves 

 and through minute apertures in the eye, while the normal function 

 of the lachrymal glands was to receive this humor from the nerves. 

 Steno discovered the minute ducts of the lachrymal glands and imme* 

 diately gave the one correct explanation of the secretion of the tears, 

 when he maintained that the tears were the produce of the lachrymal 

 glands and had their origin from the arterial blood through the in* 

 fluence of the nerves on the glands; that the normal function of the 

 lachrymal fluid was to keep the surface of the eye and eyelids smooth, 

 and that this fluid afterwards passed through the puncta lacrymalia, 

 the lacrymal canals, which have also first been observed by Steno, 

 and through the naso*lachrymal ducts to the nose, which passage was 

 only insufficient, when the lachrymal fluid was secreted in excessive 

 abundance, e. g. during the process of weeping. Finally it is worth 



