If economic historians never paid attention to gender we’d be left with many faulty assumptions. We might believe that free markets were open to all; that the value of commodities could be objectively calculated; or that uncompensated household labor flowed in seamlessly to support technical and financial innovations. Attention to gender upends each of these.
But to use this powerful historical tool, students have to dismantle their sense that male and female are obvious and fixed and come to see them as evolving historical processes in the nineteenth century. When I teach the history of capitalism, I show students how to unravel beliefs grounded in gender stereotypes—for example, that laundry is timeless women’s work, or that enslaved men cost more than enslaved women because they were stronger. With a critical approach to some key primary sources, I help them see how culture and economy shaped one another under capitalism.
A patent drawing for Eli Whitney’s “Cotton Gin” illustrates the interior mechanism and the external crank, shaped to be turned by a human hand.; Courtesy of the National Archives and Records Administration Records of the Patent and Trademark Office Record Group 241
Take, for example, the familiar crank-turned cotton gins of the 1790s, which made separating seeds from fuzzy fibers feasible, supporting the spread of slave-grown cotton across the southern United States (Figure 1). Cotton textiles, manufactured in Britain and northern U.S. states, became fashionable and popular as clothing because, more than wool, linen, or silk, they were washable. The technology/slavery/land connections in cotton’s growth are well known. But who was going to wash the newly washable clothing and make those connections worthwhile?
To answer that part of the equation, I show students another crank-turned machine that debuted in the 1790s—the “Washing Mill,” and ask them to evaluate how it might explain the expansion of the cotton industry. A trade card promises the ease with which a well-dressed young lady could keep her family’s expanding wardrobe clean (Figure 2). I ask students why the advertisement shows a girl in a flowing dress operating the machinery. They usually answer that laundry was women’s work and this is a labor-saving device for them. Yet, as they can see on this same trade card, the technology was developed for navy ships, where laundry abounded and female hands were scarce.
This trade card shows two versions of Edward Beetham’s washing mill. The young operator’s bare arms are ready for work, but her voluminous bow and flowing hair suggest that she will not toil long.; Courtesy of the Lewis Walpole Library.
I then read a printed newspaper “testimonial” advertising the washing mill, in which a husband reports that thanks to the device, his wife had to hire only a single adolescent girl to handle the washing, rather than the three adult women she usually paid. In other words, laundry was not women’s work, it was work for people under the command of others, whether common sailors or poor neighbor women. In fact, probing further, students can see that in the nineteenth-century United States, white women in the North sought to hire someone else to do the laundry (often black women); simultaneously, white women in the South sought to replace themselves as field laborers (often, again, with black women). Investigating gender connects supply to demand, through changing hierarchical labor arrangements.
Those same female field laborers, each of whom had a price, offer students ways to understand commodification, another essential part of capitalism. As a number that purported to communicate a person’s value, price was the clearest link between human capital and other forms of capital. The “prime male rate” price was and is a number used to describe a uniform commodity, wrapped around a unique human being through the processes of the slave trade (Figure 3).
With this famous image of a slave ship, anti-slavery societies used repeated uniform male bodies to underline the horror of human beings treated like property.; Courtesy of the Library of Congress Rare Book and Special Collections Division
I show students a page from Stephen Fuller’s 1788 report on Jamaica to the British Privy Council’s Committee for Trade and Commerce and ask them whether gender determined a person’s price (Figure 4). As they start to answer, their ideas of a uniform commodity fall away. They ponder the report’s overlapping price ranges for different enslaved people. A female field worker was not always priced lower than a male field worker; a midwife could cost more than a doctor. In trying to connect human skills, human labor, and price, students get a more complex understanding of how work and market intersected to create hierarchies based on sex, skill, or strength in a variety of combinations. 
In his testimony, Stephen Fuller separated enslaved people into groups based on skill, age, and sex, and linked each one with a range of prices.; Courtesy of the National Archives of the United Kingdom
Then I ask: Why are infants, youths, and the “superannuated” not separated by sex on the rate sheet? Did the sex of an enslaved person influence price only during her reproductive years? These questions lead to a discussion of the connection between childbirth and field work as valued labor when by law the children of slave mothers were slaves for life.
Finally, we tackle the question: Were enslaved children and enslaved grandparents ungendered? Students intuitively say no, but it takes time to figure out what it means to say gender mattered in lives under slavery. They have to consider how a person’s price might affect her daily life experience, either in terms of the work assigned or the knowledge of being valued differently from others and over a lifetime. But they also have to confront what value meant within different markets and along the edges of them.Students expect to find a few women working within economic history, as machine operators or cotton pickers. But showing them how to really see gender—its changing appearance, its intersection with race and class, its variable value—offers a far more powerful tool to unlock the history of American capitalism.
Students expect to find a few women working within economic history, as machine operators or cotton pickers. But showing them how to really see gender—its changing appearance, its intersection with race and class, its variable value—offers a far more powerful tool to unlock the history of American capitalism.
 Cotton has been the focus of many new histories of the economy of the nineteenth-century United States, including Sven Beckert, Empire of Cotton: A Global History (New York, 2015); Edward E. Baptist, The Half Has Never Been Told: Slavery and the Making of American Capitalism (New York, 2014); Walter Johnson, River of Dark Dreams: Slavery and Empire in the Cotton Kingdom (New York, 2013); Adam Rothman, Slave Country: American Expansion and the Origins of the Deep South (Cambridge, MA, 2005).
 Kathleen M. Brown, Foul Bodies: Cleanliness in Early America (New Haven, CT, 2009), 269. The classic work is Ruth Schwartz Cohen, More Work for Mother: The Ironies of Household Technology from the Open Hearth to the Microwave (New York, 1985).
 On commodification, see Stephanie Smallwood, Saltwater Slavery: A Middle Passage from Africa to American Diaspora (Cambridge, MA, 2008); Daina Ramey Berry, “‘We’m Fus’ Rate Bargain’: Value, Labor, and Price in a Georgia Slave Community,” in The Chattel Principle: Internal Slave Trades in the Americas, 1808‒1888, ed. Walter Johnson (New Haven, CT, 2004).
 Advanced students can consider how some kinds of lists shaped what was knowable about the value of human beings; see Caitlin Rosenthal’s article in the Winter 2016 Journal of the Early Republic.