Education (1) Mortality (1) Employment (1) History (1) Plumbing fixtures (1) Twentieth century (1) Time (1) Stock companies (1) Sixteenth century (1) Scientists (1) Rural development (1) Population (1) Plumbing--Equipment and supplies (1) Motion (1) Matter (1) Demography (1) Corporations (1) Age distribution (Demography) (1) 20th century (1) 16th century (1) Weight (1) History--20th century (1) History--16th century (1) Evolution (1) Relations with women (1) Population (1) Marriage (1) Occupations (1) Infancy (1) Growth (1)