XXVI 
THE IMMIGRATION PROBLEM 
is called particularly to this feature of the book. There 
should be noted also the colored diagram taken from 
the last Report, 1912, of the Bureau of Immigration, 
which gives by races, in very compact form, the statis 
tics of immigration into the United States from 1820 
to date. 
Altho the Reports of the Immigration Commission 
—especially, and naturally, the abstracts—form the 
chief basic material for this work, in a good many 
instances facts are given or opinions are stated for 
which no specific authority is cited. Both authors of 
the book themselves worked for four years directly 
upon this investigation; and in consequence they have 
felt justified in giving facts on their own authority 
which have not elsewhere appeared in print. 
It has not been possible in every case to give credit 
to all the individuals taking part in collecting or pre 
paring material for the Immigration Commission on 
which some of the chapters are largely based. Both 
authors had an active part in directing the work. 
In a number of cases special credit has been given at 
the beginning of a chapter to the experts of the Com 
mission who were especially active in collecting or pre 
paring material. Besides those should be mentioned 
Dr. Joseph A. Hill, who supervised the work on occu 
pations and the fecundity of immigrant women; Pro 
fessor H. A. Millis, who had immediate charge of the 
investigations on the Pacific Coast; Dr. E. A. Golden- 
weiser, who had special charge of the investigation of 
congestion in large cities; and W. W. Husband, secre 
tary, and F. C. Croxton, chief statistician, who had 
general supervision of the work of the Commission. 
In the Report of the Immigration Commission, due 
credit is given to the experts doing special work, many