244 BIOLOGY AND ITS MAKERS 
ratory and examined the sections of the dorsal cord, the par- 
ticular structure upon which Schwann had been working. 
Schleiden at once recognized the nuclei in this structure as 
being similar to those which he had observed in plants, and 
thus aided Schwann to come to the conclusion that the ele- 
ments in animal tissues were practically identical with those in 
plant tissues. 
Schwann.—The personalities of the co-founders of the 
cell-theory are interesting. Schwann was a man of gentle, 
pacific disposition, who avoided all controversies aroused by 
his many scientific discoveries. In his portrait (Fig. 74) we see 
a man whose striking qualities are good-will and benignity. 
His friend Henle gives this description of him: ‘‘He wasa man 
of stature below the medium, with a beardless face, an almost 
infantile and always smiling expression, smooth, dark-brown 
hair, wearing a fur-trimmed dressing-gown, living in a poorly 
lighted room on the second floor of a restaurant which was 
not even of the second class. He would pass whole days 
there without going out, with a few rare books around him, 
and numerous glass vessels, retorts, vials, and tubes, simple 
apparatus which he made himself. Or I go in imagina- 
tion to the dark and fusty halls of the Anatomical Institute 
where we used to work till nightfall by the side of our excellent 
chief, Johann Miller. We took our dinner in the evening, 
after the English fashion, so that we might enjoy more of the 
advantages of daylight.” 
Schwann drew part of his stimulus from his great master, 
Johannes Miller. He was associated with him as a student, 
first in the University of Wiirzburg, where Miiller, with rare 
discernment for recognizing genius, selected Schwann for 
especial favors and for close personal friendship. The influ- 
ence of his long association with Miller, the greatest of all 
trainers of anatomists and physiologists of the nineteenth 
century, must have been very uplifting. A few years later, 
