iv] of Glands and Tissues. 109 



dissecting the head of a sheep and examining the parotid gland, 

 the style which he was using, inserted by chance it would seem 

 into an opening in the duct, slipped easily down and struck with 

 a sharp clink against the teeth ; he recognized that he had dis- 

 covered the duct of the gland. Wharton as we have seen had 

 just before discovered the submaxillary duct ; but the two men 

 made very different uses of their two discoveries. Wharton 

 blundered, led away by current ideas of the nerves and their 

 animal spirits. Stensen, who had learnt from his master Sylvius 

 of Leyden the distinction between conglomerate glands, such .as 

 the salivary glands and the pancreas, and conglobate glands, 

 such as the lymphatics, laid hold of the idea that the former 

 were secretory glands and hence must all have ducts. He soon 

 found the duct of the sublingual gland, as well also as those of 

 the small buccal glands, and cleared up the problem of the 

 secretion of tears by the lachrymal gland, concerning which 

 in spite of the lead given by older anatomists there was as 

 yet much confusion. Further so far as he was able, seeing that 

 he appears to have used the simple lens chiefly and the micro- 

 scope very little if at all, and that he had as yet no knowledge 

 of the capillaries, he formed a conception of the process of 

 secretion which went very near to the truth and served as 

 a useful basis for further inquiry. 



He recognized that the material for the production of saliva 

 or of any other secretion of a secreting gland is brought by the 

 blood of the arteries and is given up in the substance of the 

 gland to the beginnings of the duct, as the blood is passing 

 from the arteries to the veins by which it leaves the gland. He 

 seems to have wanted only a knowledge of the minute micro- 

 scopic structure of the gland, and of the relation of the 

 capillaries to the secreting vesicles ; had he possessed these he 

 might have given an account of the process such as would be 

 accepted even at the present day. As it is, his views stand in 

 bright contrast to those of Wharton. Nerves, he says, serve 

 only for movement or for sensation, and the nerves of a gland 

 are of use for these purposes only. He speculates how the 

 action of the nerves by inducing movement can affect the flow 

 of saliva, and throws out the idea that it may be by bringing 



