Abstract

This paper estimates the elasticity of substitution between capital and skill in manufacturing using immigration-induced variation in skill-mix across U.S. counties between 1860 and 1930. We find that capital initially complemented both high- and low-skill labor (determined by literacy), and, unlike today, was more complementary with low-skill labor. Around 1890 capital increased its relative complementarity with high-skill labor. Simulations calibrated to our estimates imply the level of capitalskill complementarity after 1890 allowed the manufacturing sector to absorb the large wave of eastern and southern European immigrants with only a modest decline in lessskilled relative wages. This would not have been possible under the older production technology.