Growth before the Civil War:
The Antebellum Puzzle of Increasing Incomes and Decreasing Heights

Philip R. P. Coelho, Ball State, and Robert A. McGuire*, Akron
*Department of Economics
University of Akron
Akron OH 44325-1908
Telephone: 330-972-7521 Fax: 330-972-5356

The current economic history literature on living standards in the pre-Civil War United States has two contradictory strands. One is that income (both total and per capita) in the United States experienced secular growth from soon after the War of 1812 through 1860. The other strand is the anthropometric evidence of a decrease in heights starting with the birth cohort of the 1830s and possibly earlier. The anthropometric data appear to be well founded, so there is a puzzle: Why did heights decline as incomes rose? One school of thought suggests that when well being (welfare) is assessed we should rely on "biological" measures, because current measures of nineteenth century income are inadequate. Traditional measures of the level of income may over estimate the true growth of income, and they may not accurately measure the distribution of income, and especially the distribution of food resources, over the entire population.

As an alternative explanation for the "antebellum puzzle," we emphasize the biological consequences of economic growth prior to the twentieth century. We suggest that the disease environment deteriorated nationally even as incomes rose. The deteriorating disease environment resulted in a fall in the mean heights of the population. Regional diseases predominated before the nineteenth century. These regional diseases, both from within the nation and from abroad, became more widespread throughout the United States during the nineteenth century. The integration of disease pools took place for four reasons. 1) The growth in population increased population densities, and the increased biomass (both human and non-human) facilitated the transmission of disease-bearing pathogens. 2) The growth of great cities (apart from the general increase in populations) allowed diseases to exist where before they would not have long survived. Cities provided a habitat and a focal point for spreading diseases that had previously been unknown or episodic in the United States. 3) The declines in the rigors, time, and money costs of transportation allowed the sick, infected, and asymptomatic to travel vast distances, infecting people along their routes and at their final destinations. 4) Beginning in the early nineteenth century declines in transport costs and times initiated a movement of populations across continents and oceans; these migrations (both foreign and domestic) exposed both natives and migrants to new disease ecologies. The migrants were exposed to diseases that were new to them, but native to the ecologies of their new homes. And the migrants brought their diseases with them, adversely affecting the natives of their new homes. Both results occurred because populations exposed to diseases that they had not previously experienced suffer much more than populations constantly exposed to these diseases. Foreign immigration as well as internal migration changed the disease ecologies for both migrants and natives.

Our explanation for the "antebellum puzzle" relies upon the fundamentals of economics and biology, arguing that a virtuous economic growth cycle was offset by a vicious biological cycle. Wages are related to the increased output (the marginal contribution) that is attributable to an additional worker multiplied by the change in total revenue (the marginal revenue) the additional output secures. We accept as givens that, in the first half of the nineteenth century, there were both a secular increase in economic output and a decline in heights. We attribute the growth of wages and incomes during the period to an increasing population that led to increased specialization and integration of economic activities. Increases in population led to increased markets that induced greater specialization and productivity. Growing markets and incomes increased the demand for transportation services. This increased demand made profitable the creation of a network of high-fixed-cost modes of transport with low variable costs. Given the volume of traffic, these high-fixed-cost, low-variable-cost modes allowed substantial reductions in the overall costs of transport, from 1/5 to less than 1/10 the previous ton-mile charges. The result was a substantial widening of the market.

The major difference between this explanation of economic growth and Adam Smith’s is that we explicitly incorporate feedback effects. Increases in population increase market size, and the increased market size affects how production is organized. The increased specialization led to rising output (and wages) per worker, as production costs fell. Because of its role in the transmittal of diseases, and because it is an input into many other sectors, we focus upon transportation developments. Increased market size led to more specialized modes of transport that had lower average costs given the increased volume of goods (and passengers) they carried. The reduction in the average costs of transport led to further increases in market size that stimulated still more specialized transport services and further declines in costs. More and more specialized modes of transportation led to increased market size, both directly because of lower fares, and indirectly by attracting more settlers. This is the virtuous cycle of economic growth. Extensive growth increased market size: increased market size led to more specialization and greater output per worker. The increased income led to a further increase in market size.

Offsetting this virtuous cycle of "Smithian" economic growth was a vicious biological cycle. Increased market size also provided a resource for the pathogens that parasitize humans. In the centuries before the twentieth, an increase in human density was always associated with substantial increases of biological resources for micro-parasites. With increased densities and cities came animals that provided humans with transportation and food. Both humans and other animals excreted waste products that were not subject to sanitary disposal. These waste products contaminated water supplies and soils, exposing people to the diseases they harbored; they also were ideal breeding grounds for opportunistic infestation by "new" microbial pathogens. Along with the increased animal populations came plant foods that fed humans and their animals. These plant foods, in the absence of modern storage and packaging attracted their own set of microbes and vermin that harbored and spread pathogens. The result was that the total biomass available to pathogens increased exponentially because of: 1) the increase in human numbers and density; 2) the concomitant increase in domestic animals; 3) the increased organic wastes that humans and their animals generated; 4) the increase in plant foods stored next to humans and their animals; and 5) the vermin the increased biomass attracted.

We explicitly recognize the paradoxical role of increased incomes in the transmission of diseases. Increased income led to an increase in demand for both more food and "higher quality" foods. ("Higher quality" here refers to foods derived from animals: meat, milk, cheese, and so forth.) The increases in the urban populations and incomes led to a more than proportional increase in the demand for animal products. This, in turn, led to a more than proportional increase in the urban biomass available to disease causing microbes as the animals, plant foods, and the waste products associated with them increased. Increasing incomes had a positive effect on the biomass, such that the total increase in the biomass was proportionally greater than the increase in the human population.

The increased biomass surrounding human communities allowed pathogens to become more abundant, and increased human densities facilitated the transmission of infectious diseases. As infectious diseases became more rapidly transmitted and widespread, more people were sick more often. The decline in transport times and costs abetted this process; the consequences were an increase in diseases nationwide. The resultant increase in human morbidity and mortality associated with these pathogens had their impact throughout the "industrializing" world in the nineteenth century. The American experience was just one aspect of a worldwide phenomenon.

The integration of disease pools (both foreign and domestic) began early in the nineteenth century. Steerage fares across the Atlantic fell almost 70 percent between the teens and the early 1830s on ordinary trading ships. Packet ships had regularly scheduled sailings across the Atlantic by the end of the 1820s; their fares were about 50 percent less than the earlier fares on trading vessels. Within the United States, coastal packet ships, steamboats, and canals led to substantial declines in the costs of transport, and concomitant increases in the volume and frequency of interregional traffic. On the Mississippi in 1830 an upstream passage by steamboat from New Orleans to Louisville took less than 10 days, and passenger fares were 26 percent of the 1815 rates. As the lower Mississippi became settled with slave plantations, it generated an increase in demand for shipping services. The subsequent increased specialization in the transport sector led to falling costs. The transmission of malaria from its reservoirs in the plantation South to the Midwest becomes obvious. River traffic facilitated the spread of malaria, as infected humans traveled from the South to the Midwest. Because malaria’s latent period is from 9 to 16 days, passengers or crew could leave New Orleans or Vicksburg and be in Cincinnati before they knew they had the disease. Malaria was just one of the diseases that were dispersed as markets and regions were integrated.

The early nineteenth century saw: 1) a rapid increase in population density; 2) the growth of great cities; and, 3) rapidly increasing external and internal migration. Population densities of the states increased rapidly between 1800 and 1860. Examples are: the population density per square mile of Pennsylvania in 1800 was 13.4, in 1860 it was 64.8; for Virginia the same data are 13.7 and 24.8; for Massachusetts, 53.6 and 153.1; and finally for Ohio 1.1 and 57.4. The urban population of the United States grew from 6 percent of the total population in 1800, to 8.8 percent in 1830 and to 19.8 percent in 1860. Immigration of Europeans (with their different diseases) increased geometrically in the 1820s, 1830s, and the 1840s. Many of the immigrants settled in the cities, establishing disease reservoirs there. Cholera and typhus epidemics regularly followed the arrival of infected immigrants in the mid-antebellum period. Westward migration across the United States was well under way in the antebellum period as well.

Continual exposure to the spread of the diseases produced surviving populations over time that had more acquired immunities (antibodies) in the various regional and urban disease environments. This was the beginning of the transition from epidemic diseases to endemic (childhood) diseases. The normal course of this transition was altered after the Civil War decade with the advances in public health, hygiene, and the distribution of foods that ameliorated the effects of the deteriorating disease environment that had been part and parcel of economic growth. The last third of the nineteenth century was the period of Pasteur, piped water, sewage treatment, and refrigerated transportation. These advances, as well as the emerging acquired immunities, lessened the deleterious anthropometric effects of diseases.

The diseases that afflicted humanity during the nineteenth century were not all deadly, some, like malaria, killed few of their victims, but simply infected humans, sapped strength, and lived with their human hosts. More explicitly, the case mortality rates of these "morbid" diseases were quite low. This does not mean that their economic effects were negligible. Diseases such as malaria, hookworm, arthritis, rheumatism, pleurisy and gout have major economic effects while still having low rates of case mortality. These diseases linger and may recur, significantly reducing the value of labor of the people afflicted. Because these diseases are not dramatic, they become like background noise: unnoticed and unremarked. Yet many of these morbid diseases have had a greater impact upon the American economy than the dramatic killer diseases like yellow fever, cholera, or rabies. Death and dying are dramatic, while living in pain is the common condition of humanity. As a result there are few historical traces of these non-dramatic diseases, but what evidence there is corroborates the negative economic effects of these non-lethal debilitating diseases.

Debilitating diseases reduce economic productivity, but in the context of the nineteenth century economy, what they did was reduce the rate of growth that would have happened in their absence. The debilitating diseases were primarily soft tissue diseases that leave few traces in skeletal remains; consequently physical evidence for them is difficult to find. The evidence that does exist consists of their identification in contemporaneous records and their universality in the medical records of the twentieth century.

The American South played a crucial role in the disease narrative. The South was home to some of the most debilitating diseases that were transmitted to other parts of the United States. These diseases were endemic to the South, and the South was the foci for them. Southern slavery played a significant role in the preservation and spread of these diseases. A large portion of the slave population lived in closely packed quarters confined on relatively large plantations. The institution of large-scale plantation slavery as it was practiced in the American South consequently provided reservoirs that allowed diseases to spread throughout the country. This was an important, yet neglected cost of slavery. Hookworm and malaria are two of the primary "southern" diseases; they are both soft tissue diseases with low case moralities. The low case mortalities mean that contemporaries did not single out these diseases for special attention. Indeed, hookworm was not even recognized as an infliction by most medical practitioners until 1903.

Malaria, however, was recognized and rampant throughout most of the Midwest until after the Civil War; and both malaria and hookworm were widespread in the nineteenth century South. These diseases affected labor efficiency by their debilitating nature, and they had a non-trivial impact on the physical growth and development of the people that were infected by them. Malaria and hookworm have deleterious affects on newborns and infants, and both can significantly affect the physical measurements of adults who had the misfortune to be infected with these pathogens as children.

Evidence on the incidence of malaria is available in abundance, but the evidence has to be treated with care because the disease causing protozoa were not identified until 1880, and this knowledge was not widely accepted by the American medical community until nearly the twentieth century. Even then the protozoan vectors and their life cycles were not discovered until after the turn of the century. This means that when historical evidence for the pervasiveness of malaria in the Midwest is found, the data has to be treated carefully. The diagnosis of malaria was haphazard, at best, until after the turn of the twentieth century.2 Hookworm, while probably afflicting more people than malaria in the South, has left fewer historical traces. Hookworm was unknown in the United States before the twentieth century until 1903 when it was discovered to be virtually hyper-endemic in the South, with an estimated 40 percent of the population infected with hookworms. Since both hookworm and malaria affect a large proportion of the population in areas where they are endemic, we expect human productivity to be reduced in places where they exist either jointly or singularly.

But diseases do not equally affect all populations, and malaria and hookworm are not exceptions to this rule. Certain ethnic groups are more refractory to infection than others. People of tropical West Africa origins are more resistant to hookworm and malaria than are people of European descent; there is no reason to think that this ethnic disparity did not exist in the nineteenth century. Consequently, when the impact of the spread of diseases on anthropometric or productivity measures is examined, we have to examine the effects of diseases on each of the two major ethnic groups in the South separately. Of the two populations in the American South, the "white" population was of predominately European ancestry and classified as free, and the "black" population was of predominately African ancestry, and generally enslaved. These ethnic differences mean that any analysis of changing stature or productivity has to account for the differential impact of diseases.

For example, when comparing changes in stature or labor productivity of free and slave populations in the South, it is a comparison of a relatively healthy slave population to a relatively morbid free population because the southern disease ecology was relatively more detrimental to whites than to blacks. Thus a simple black versus white comparison is not valid. There are more than two categories (free versus slave, or black versus white); there are, at least, four categories (healthy white, healthy black, morbid white, morbid black). There are additional complications as well; one such complication is the effects that the dramatic changes in slave demographics had upon the disease ecology before and after 1807 (when the international slave trade was banned). The importation of many West Africans prior to 1807 meant that West African pathogens also were brought over. This changed both the population characteristics of American slaves and the disease ecology they and other southerners experienced. Before 1807 the disease ecology of the South was deteriorating, and especially the disease environment American slaves faced because they were relatively more exposed to the imported diseases. And the imported Africans were exposed to a new (to them) set of American pathogens. After 1807 both American-born and African-born blacks gradually acquired immunities to the prevailing disease ecology of their regions. Consequently blacks and whites, northerners and southerners, faced different disease experiences, and these experiences were historically different. In general, climate, urbanization, developments in transportation, and increasing population densities differentially affected people of different ethnic groups and people of different regions. In explaining the impact of diseases upon populations this diversity must be recognized. One size does not fit all.

In this paper we: 1) explain the interactions of extensive and intensive economic growth, and how these affected the growth of the transport network of the United States; 2) examine how the changed transportation network facilitated the spread of disease; 3) explain how the growth of population density and cities, and increased population movements aided the spread of diseases; 4) assess the economic impact of increased morbidity; and 5) relate these developments to the institution of plantation slavery in the American South. We show that both heights and labor productivity varied with the disease environment, and that the variations also manifested themselves in ethnic groups. The data are consistent with the hypothesis of increasing economic output per person and deteriorating disease ecology. The simultaneity of increased productivity and increased diseases is explicable, and is fully consistent of what we know of the economy and the anthropometric data.

Advocates of the "biological" approach to estimating living standards (essentially relying upon anthropometric measures rather than economic data) have challenged those who stress the importance of the disease ecology to provide testable hypotheses and evidence that are consistent with the phenomenon of declining stature and the "Antebellum Puzzle." We answer that challenge by explaining the aforementioned relationships between extensive and intensive economic growth, and economic growth and increasing morbidity. We then relate the hypothesis to the changing disease and economic ecology of America in the nineteenth century prior to the Civil War.


1 See the anthropometric studies of John Komlos, Robert Margo and Richard H. Steckel, John E. Murray, Steckel, and Steckel and Donald R. Haurin, among others.

2 Although the diagnosis of malaria was not scientifically accurate, there is no reason to believe that it was biased upwards. Malaria was frequently misdiagnosed.