Steam Economies (2021)
Latent
mid-15c., "concealed, secret," from Latin latentem (nominative latens) "lying hid, concealed, secret, unknown," present participle of latere "lie hidden, lurk, be concealed," from PIE *late-, suffixed form of root *lādh- "to be hidden" (source also of Greek lēthē "forgetfulness, oblivion," lēthargos "forgetful," lathre "secretly, by stealth," lathrios "stealthy," lanthanein "to be hidden;" Old Church Slavonic lajati "to lie in wait for"). Meaning "dormant, undeveloped" is from 1680s, originally in medicine.
Online Etymology Dictionary.
L=Qm
L = specific latent heat of a substance
Q = energy released or absorbed during phase change
m = mass
(Formula for latent heat)
Latent heat can be understood as energy in hidden form which is supplied or extracted to change the state of a substance or body without changing its temperature.
The sugar technologist, chemical engineer, and inventor Norbert Rillieux (1806) recognized that the economy of steam could be produced through the recurrence of latent heat in steam and vapors. Rillieux’s notable invention was the multiple-effect evaporator under vacuum. A system that was designed for efficiently using latent heat from steam to evaporate water or in the case of Rillieux sugar cane juice and transform its body into crystalline form.
Before Rillieux's invention, nineteenth-century sugar processing was limited to the Sugar Train, Jamaica Train, or Spanish Train method. In these systems, the labor of enslaved people ladled boiling sugar juice from one open kettle to another. Throughout this process some sugar was lost because of spillage, and since there wasn’t an efficient procedure to monitor the heat levels of each kettle a significant amount of sugar was burned. This system was dangerous for workers who would suffer from burn injuries, and it caused considerable high costs in fuel because of its inability to regulate heat. The multiple-effect evaporation system was a safer, cheaper, and more efficient way of evaporating sugar cane juice.
Rillieux would work on his invention for over a decade before he was hired to install the system on the Belle Chasse Plantation. This particular plantation was owned by Judah Benjamin who at the time was a lawyer but would later serve for the Confederacy as Secretary of War. When Rillieux arrived to install his invention on Louisiana plantations in the South he did so as a “consultant” but under the law, he was still a Black man who could only reside, enter and sleep in the same quarters as those who were enslaved.
Rillieux installed several multiple-effect evaporation systems across the South of the United States until 1855. The multiple-effect evaporation system that is designed by Rilliuex posits the relationship between black liberation and black invention. The primary drive for invention has always been need (necessity is the mother of invention). But is any invention liberated under the grips of capitalism? The workers who operated the Sugar Train method are not entirely liberated through Rilliuex’s invention. Their exploitative labor was relieved from taking on sugar processing but they had to do some other dangerous task. They no longer have to endure the pain of that former labor but they were still not liberated. Norbert Rilliuex has a complicated history. However, he lived within complexity and navigated the Antebellum South carrying that complexity and ambivalence.
The chemical engineer and the creation of his multiple-effect evaporator sits somewhere between heroic myth and alchemy. The process of purifying, refining, sampling, and harnessing energies that lie hidden in form, yields a generative site to reinvent knowledge in the plantocratic laboratory.
