Subject
History
6
Conduct of life
5
Slavery
5
Indians, Treatment of
4
Working class
3
Description and travel
2
Labor
2
Labor movement
2
Animal welfare
1
Aphorisms and apothegms
1
Business ethics
1
Industrial relations
1
Laboring classes
1
Political science
1
Politicians
1
Politics, Practical
1
Railroads
1
Social conditions
1
Women
1