This semester I’m lucky enough to be co-teaching an undergraduate research seminar, “Commodities of Colonialism in Africa,” with my advisor, Dr. Bob Harms. The course explores the histories of four commodities—cotton, rubber, ivory, and diamonds—the demand for which partially drove Europe’s colonization of Africa. So far, our readings have taken us from Mozambique to Manchester, from Kinshasa to Akron. By the end of the term, students will write their own research papers based on a commodity from Africa. They’ve picked fantastic topics and I can’t wait to read them.
A few weeks ago, to acquaint students with primary sources and the process of reading archival materials “against the grain,” I brought to class a few sample sources from my own research. Provided with some context, students were to tell a narrative based on the sources, and to identify some questions that the narrative left unanswered.
We often have to condense these types of close analyses within chapters or publications, but sometimes just a few letters can offer revealing lenses into the past. In this case, we’ll see the extraction, exchange, embrace, and erasure of indigenous botanical knowledge, all in four letters over the course of ten months.
As context: beginning in the early 1880s, men and women in West Africa harvested liquid latex from vines and trees growing wild in the forests of the Asante empire, which Britain conquered in the late nineteenth century. Thereafter, Asante became part of the Gold Coast, the British colony that in 1957 would gain independence to become Ghana. During the turn-of-the-century global rubber boom, Gold Coasters coagulated the latex into solid lumps, biscuits, and sheets, which porters carried from the Gold Coast’s forests all the way south to the coast—a trek of up to 200 miles. By the end of the nineteenth century, the Gold Coast was exporting more rubber than any other colony in the British empire.
But in the first years of the twentieth century, British colonial officials began stressing over the declining quality of the colony’s rubber yields, which increasingly tended to be watery and soft, and consequently drew low prices from British and American buyers. Staff in the colony’s Department of Agriculture held that if they could determine the coagulation method that yielded the highest quality rubber, then traveling instructors could train Gold Coasters to produce better rubber. So, to perfect methods to coagulate latex, the Department of Agriculture collaborated with the London-based Imperial Institute, which in the late-nineteenth century became the hub for research meant to advance the commercial development of resources in Britain’s empire.
On Christmas Day, 1908, an officer, A.E. Evans, of the Gold Coast Department of Agriculture wrote to the Director of the Imperial Institute, Dr. Wyndham R. Dunstan, about a “new process” by which latex could be coagulated:
I beg to inform you that I am sending to the Imperial Institute under separate cover two boxes containing Funtumia Rubber coagulated by a new process. Also a small quantity of the liquid used in the coagulation of same. I shall be pleased if you will furnish this Government with a report as to its commercial value.
The latex is coagulated within two or three minutes by adding a very small quantity of the Diecha juice to the pure latex and stirring: no heat is required. The process is absolutely no trouble.
Evans’ brief note did not elaborate on how he came to know of this “new process,” nor who told him the name “Diecha” juice. These are the types of exchanges the archive leaves silent.
A few months later, an Imperial Institute staff member wrote to the Gold Coast’s Director of Agriculture, WSD Tudhope, to request more information about the mysterious “Diecha” juice:
Mr. Evans states that the rubber was prepared by adding a small quantity of “Diecha” juice to the latex. I shall be interested to learn the botanical name of the “Diecha” plant, or, if that is not known, to receive botanical specimens for identification (March 5, 1909).
The Imperial Institute wanted to fit “Diecha” onto its taxonomic chart, to label it with a scientific name, to incorporate the species into Britain’s botanical empire. But the “Diecha” juice forwarded by Evans evaporated during transit from the Gold Coast to England, preventing its properties from being evaluated by chemists at the institute. The global circulation of botanical specimens during this era of rising mobility—fueled in part by rubber—was far trickier in practice than sometimes we are led to believe.
In a matter of months, Tudhope shipped to the Imperial Institute more “Diecha” juice, along with twigs and leaves of the vine from which it was extracted. With the package, he enclosed a letter from one of his African employees, left unnamed, who offered more information about the vine’s classification in Twi, a language widely spoken in the Gold Coast:
The vine is called Di a etcha…this will be written in vernacular thus: Di a etwa…which is an exaggeration to the action of the latex and is known as Omatwanini, common pronunciation Omartchaninie (August 10, 1909).
Tudhope attempted to make sense of what the Twi name could mean. Indeed, omatwanini offered some clues about the mystery species, which Tudhope conveyed to the Imperial Institute:
Its common name ‘Omartcha-ninie’ (Twi) would seem to indicate it is a species of Strophanthus. The native name for Strophanthus I find is ‘Omartcha,’ and ‘ninie’ means male, i.e. Omarthca-ninie, or male Strophanthus.
From my native officer’s description of the plant (should this be correct) it would seem to be a monstrous variety of Strophanthus, and probably new to science (October 1, 1909).
If you skimmed that, I urge you to read it again. It’s just a short letter talking about plants you’ve probably never seen and a language you may never have heard of. But seriously, take a look at what is going on here: a reasonably powerful colonial official is drawing on indigenous botanical knowledge (as reflected in Twi nomenclature) to report to the metropole’s epicenter of imperial science what he believes to be a novel scientific discovery.
In one fell swoop, Tudhope recognizes a sophisticated knowledge regime that classifies plants by genus and sex… yet he defines that knowledge as not quite “science,” which he insinuates is that which is advanced by non-Africans. In much the same way, Evans, in his letter (above), had described coagulation-via-“Diecha” as a “new process”—but to whom was it new? It’s highly likely that he learned it from experienced Gold Coast rubber workers.
In four letters, exchanged over ten months, we see the extraction, exchange, and embrace of indigenous knowledge, as well as the delimitation of a narrow “scientific” knowledge.
I want to be clear that we don’t see the production of knowledge in these correspondences: we don’t see African tappers and rubber traders experimenting with different “juices” to identify which coagulates latex effectively, and we don’t see them observing similarities across different species in forests and naming them accordingly. The archive reveals but does not state that coagulating latex into rubber by adding the juices of omatwanini vines was an African innovation, appropriated and scrutinized—but certainly not discovered or invented—by the colonial government. If “Diecha” was a mystery in 1908/1909, it was only a British one.
Six months later, in a fifth letter, Tudhope received word that the Imperial Institute had identified the omatwanini vine as Strophanthus preussii. But anytime its juices were shipped back to London, they evaporated en route, and when the institute tried to test and “prove” the coagulating capabilities of the di a etwa juices, it found that “the coagulation of the latex appeared to be retarded rather than accelerated by the addition of the ‘Diecha’ juice” (July 10, 1911). Unable to replicate the method in its laboratories, the Imperial Institute was unwilling to acknowledge its efficacy.
What are the lessons learned from the case of the “probably new to science” “Diecha” vine?
The supremacy of a Latin name, the dismissal of an indigenous method: these too were the violences of colonialism. Yet, careful research and archival sources can hold the potential to restore erased ingenuity, if we read them with a commitment to grappling with their silences, to interrogating their prejudices, and to exposing their injustices.
*Correspondences discussed here can be found in a slim folder labeled AY 4/1988, “Funtumia Rubber, Gold Coast: Examination of Samples” at The National Archives in Kew, Greater London, UK.