144 THE HISTORY OF BIOLOGY 



whom may be specially mentioned the German Michael Lyser, who as 

 prosector used to perform Bartholin's most important dissections, and after- 

 wards became professor at Leipzig. A number of valuable works were pub- 

 lished by Bartholin in the sixteen-fifties, but his productive powers very 

 soon waned. After Lyser's resignation from the post of prosector (1651) 

 little occurred there in the way of fresh anatomical results; as early as 1660 

 Bartholin was completely relieved of all instructional and examination work, 

 and then he had only his membership of the board of the university, of which 

 he seems to have taken advantage mostly for the pui-pose of providing his 

 relations with good appointments. With this end in view he is believed to 

 have passed over deserving pupils, including Steno, who is mentioned later 

 on. Other not very attractive characteristics of his are also mentioned, such 

 as that, physician though he was, he once fled from the city during a plague 

 for fear of infection and retired into the country; again, the way in which 

 he procured extra salary from the Government caused him to be censured on 

 several occasions. His writings abound in expressions of the most extravagant 

 self-praise, though he displays in them a really genuine respect for science — 

 undoubtedly the most attractive trait in his character. He died in 1680 and 

 was succeeded by his son Caspar, who carried on his work, reaping a number 

 of external honours, but in no wise possessing his father's merits. 



Bartholin discovers the lymphatic system 

 Thomas Bartholin's most important achievement is generally considered to 

 have been his clearing up of the mystery of the lymphatic duct system. He 

 was not aware of Pecquet 's discovery when he began to study the chyle 

 vessels (lacteals), and therefore believed, with Aselli, that they led to the 

 liver. By observation and experiment, however, he soon found that this was 

 not so and at the same time discovered that these vessels were connected 

 with a vascular system distributed throughout the entire body, and con- 

 taining a fluid clear as water. These discoveries he described in a treatise 

 which came out in 1653, in which he declares that the liver cannot perform 

 the blood-forming function which classical anatomy had ascribed to it; nor, 

 since the chyle vessels do not connect with the liver, but on the contrary a 

 number of lymphatic ducts go in the opposite direction, can the food be 

 converted into blood in the liver, as the anatomists up to the time of Harvey 

 and Aselli, and the two latter as well, had concluded. He closes his essay 

 by erecting a monument to the liver, the body's now dethroned ruler, in the 

 form of a parody of the high-falutin memorial speeches which it was the 

 custom of the time to make in honour of the distinguished dead. 



Bartholin set great store by his discovery of the lymphatic system and 

 wrote several fresh articles on the subject, without, however, making any 

 very important additions to his first account. The rest of his scientific literary 

 work, which is rather extensive, cannot be compared from the point of view 



