PREFACE 



Gbts booh is more especially 

 intenoeb for mv. professional 

 frtenbs wbom If bave met 

 ourtna mv. travels in biffer= 

 ent parts ot tbe worlb, ano 

 to wbom IF am cbteflv ln= 

 bebteb for manv courtesies 

 anb mucb information. (Tbe 

 teit consists of a sertes of 

 articles publisbeb in £be 

 Journal of tbe Hmerican 

 /IBcbical association burtng 

 tbe last six montbs of tbe 

 sear past. /Iftanv new illus= 

 trations bave been abbeb 

 wbicb tbe autbor bopes will 

 enbancetbe value of tbe booh 



N. SENN 

 Chicago, June 15, 1905 



