November 5, 1920] 



SCIENCE 



421 



was spent in Hoppe-Seyler's laboratory, mader 

 the master himself and his assistant Baumann, 

 in working through the form.er's well-known 

 text-hook in physiological chemistry. In ad- 

 dition, time was found to attend von Eeckling- 

 hausen's autopsies and demonstration course, 

 although at this period no further courses 

 were taken with this master of pathology and 

 for the reason that Welch concluded that 

 until a grounding in normal histology was 

 secured, it would not be profitable to pursue 

 pathological histology. 



The summer semester at an end, Welch left 

 Strassburg for Leipzig, the summer vacation 

 being spent with a friend in a pedestrian tour 

 in Switzerland and northern Italy. It is of 

 interest to inquire just what was the lure of 

 Leipzig. Obviously Waldeyer was the attrac- 

 tion in Strassburg; now it was Heubner and 

 Wagner who drew the student to Leipzig. At 

 that time Heubner had not entered the field 

 of pediatrics in which he afterwards became 

 celebrated, but he was working rather in the 

 field of neurology; and, indeed, it was his 

 imjKirtant book on the diseases of the blood 

 vessels of the brain,^ which Welch had read, 

 that determined the choice. If we undertake 

 to penetrate further into the source of Heub- 

 ner's attraction for Welch, we are led back 

 to the days at the College of Physicians and 

 Surgeons in 'New York and the lectures of 

 Seguin which had exerted a strong influence 

 on Welch, so that if we had then inquired 

 whither he was tending in medical specializa- 

 tion we should have discovered that he was 

 looking to diseases of the nervous system as the 

 field for practise, while pathology remained 

 his main interest and subject of training in 

 Germany, although he could not then antici- 

 pate its pursuit as a means of livelihood on 

 his return to America. 



Circumstances were, however, to defeat this 

 consciously worked out program. In due 

 course Welch subscribed for Heubner's course, 

 only to find very quickly that the latter was 

 not then interested in teaching; soon the 

 course began to languish and the students to 



2 Heubner, ' ' Die luetisehe Erkrankungeu der 

 Hirnarterien, " Leipzig, 1874. 



absent themselves, and it was not long imtil 

 Welch was looking elsewhere to fill his time. 

 Wagner, who later succeeded Wunderlich in 

 the chair of internal medicine, was at the time 

 professor of pathological anatomy. Welch 

 found Wagner's courses and the opportunities 

 afforded for independent work by his institute 

 admirably adapted for his own purpose. 

 Here he attended autopsies and obtained 

 specimens of tissue for microscopic exami- 

 nation. At first the blocks were given as a 

 favor; but later, Wagner's interest having 

 become aroused, he would personally select 

 the specimens for examination and for report. 

 In this manner Welch occupied his mornings; 

 the afternoons were, however, still free. He 

 attended Wagner's polyclinc, which kept him 

 in touch with practical medicine. 



At this period Ludwig's laboratory was the 

 center of attraction for the talented men in 

 Germany and also for many foreigners espe- 

 cially interested in physiology. Welch de- 

 cided to offer himself and was accepted by 

 Ludwig. That the choice was a propitious 

 one is shown by the group of men at that 

 time working with Ludwig and with whom 

 Welch was now associated. The first assis- 

 tant was the gifted and inspiring Kronecker 

 with whom Welch formed an enduring friend- 

 ship. Among foreign students was Pawlow, 

 and Drechsel and Flechsig were in charge of 

 the chemical and the histological divisions of 

 Ludwig's laboratory. Welch was set by Lud- 

 wig to study the ganglia and nerves of the 

 auricular septum of the frog's heart with the 

 gold chloride impregnation method, in the 

 course of which he actually brought into view 

 the ganglionic cells with T-shai)ed fibers 

 which Eanvier described in detail somewhat 

 later. The semester closed and the usual 

 Ahschied supper was given by Kronecker. 

 Of course Welch was invited and there was 

 characteristically exhibited a model of the 

 ganglion cells with fibers both entering and 

 leaving it — a novel and as we now know a his- 

 tologically highly important event. 



The first year of Welch's European study 

 was now over. It had been spent in pre- 

 paring himself in normal histology, physio- 



