THE PRE-WAR QUARTER CENTURY 1 
major conclusions reached in the chapter may be summarized as 
follows: 
Sensitiveness of Migration to Business Conditions. 
1. A comparison of data pertaining to male immigration, pig 
iron production, and factory employment, in the pre-war period, 
reveals the fact that cyclical fluctuations in male immigration are 
ordinarily associated with prior changes, in the same direction, in 
production and employment. 
Inasmuch as good employment conditions would presumably 
encourage the prospective immigrant and also increase the instances 
in which friends and relatives in this country would remit funds for 
the journey, we may reasonably assume that the observed close 
relation is not a mere coincidence but that business conditions are 
in fact a dominating determinant of cyclical fluctuations in im- 
migration. 
2. The influence of a major cyclical change in industrial con- 
ditions is usually apparent in immigration within less than a half 
year. 
3. The cyclical movements in emigration are inversely correlated 
with those of immigration and employment, with large emigration 
in depression periods and relatively small emigration in boom periods. 
4. The fluctuations of net immigration exhibit a high degree of 
sensitiveness to employment conditions in the United States. This 
is evident when immigration and emigration are jointly considered, 
either in terms of the ratio of emigration to immigration, or in terms 
of the numerical excess of arrivals over departures or of departures 
over arrivals. 
Relative Volume of Migration and Changes in Employment. 
When we turned from a consideration of the direction and timing 
of turns in the cycles of immigration and emigration to the some- 
what more concrete problem of the relation between the volume of 
immigration, gross or net, expressed in number of persons, and the 
concurrent change in the number employed or unemployed, we 
found, partly because of the diversity of the possible bases of 
comparison, a somewhat less secure basis upon which to form un- 
equivocal conclusions. For example, the conclusions reached in 
comparing cumulative immigration with the change in employment 
or unemployment are materially affected by the length of the period 
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