The Role of Cannabis Sativa in Global Trade
By Mike Ryan
A sixteen-inch cable was made from the Sunn in 1802, by that patent, laid down as a mooring cable at Gravesend the whole winter and, after various examinations, by cutting off the clinches, upon different ships taking it in as moorings, for five months in succession, it was found so fresh and good, that it went in the last ship that rode by it to India as a working cable.1
An English sea-captain, providing this statement at the beginning of the nineteenth century, lauds the properties of a certain fibrous plant that was essential to the development and promulgation of overseas trade around the world. The Sunn, as described in the passage above, is a specific strain of a certain plant. Though that strain is native to Bengal, the plant had its origins in China and has spread throughout the world, thriving in a variety of conditions.2 This plant, absolutely necessary in the history of world trade, is commonly known as hemp, Cannabis sativa. (See figure one.) Though C. sativa is more infamous for its hallucinogenic properties, the plant's other, practical, uses are of utmost importance in the history of the world.
Due to its botanic properties, hemp can be fashioned into many useful items. Hemp clothes are fashioned today, but the problem with them is that they are coarse and scratchy. Clothing made of hemp is neither as pliable nor as comfortable as that made of linen or wool. Though hemp clothes will protect the wearer, they have more ceremonial aspects about them; to wear a hemp shirt is to be in mourning, in despair.3 The more endearing, and useful, quality of hemp is the exact reason why it makes less than comfortable clothing. "The presence of lignin, the material that strengthens wood, in and around the cellulose fibers,"4 makes it better used as a material with which one can make cords and ropes. Hemp fibers, when properly prepared, can grow very long and can make extraordinarily sound ropes. (See figure two.) The individual fibers that would be prepared into hemp rope were very valuable and worth a great deal for both national and economic identities, as shall be discussed below.
To prepare hemp for cable production, one had to remove the gum that bound each individual hemp fiber to another and to the main, woody stalk. The way to do that was to put it through a process known as retting, which differed depending on the location where the hemp was grown and prepared.5 In late eighteenth and early nineteenth-century America, for example, hemp was "dew-retted", which meant that the hemp stalks, after having been harvested, would be thinly spread on the ground and left to sit in the open for three to four weeks, with only an occasional turning. Though the gum would be removed by this process, the hemp fibers would also be substantially weakened, thus producing rope with lower tensile strength.6 More meticulous ways of harvesting, preparing, and retting the hemp fiber would result in a hemp rope that was stronger and more enduring and would fetch a much higher price in the world's markets.7
The spread of hemp from its origins in Asia was generally westward and occurred gradually over hundreds of years.8 Hemp's arrival in Western Europe meant another crop for the populace to use, whether for practical or narcotic purposes. Thorough experimentation (see figure three) of the plant's properties, both in a logical, scientific manner and through the general experience achieved through trial and error, allowed for further developments in the European hemp industry. Indeed, certain regions in Europe became prime areas of hemp production.9 However, hemp's presence in Europe meant further opportunities for the continent's political and cultural expansion into other parts of the world. Indeed, the growing of hemp became a primary key to further expansion and colonization; to grow hemp was of primary importance, a matter of national, political, cultural, and economic destiny.10 Ships that were outfitted with well-crafted hemp ropes and sails could sail to and from entrepôts with much greater speed and less risk that the moorings would snap in ill weather. Hemp, in a cyclical manner, was a trade goods that was a vital product for the continuing development and refinement of the trade industry itself. Hemp was a product that was tied up, in the early modern era, with the trappings of proto-nationalism, an impetus to trade and worldly domination by the European powers. A quote from the same English captain who explained the strengths and soundness of the Sunn hemp in the beginning of this paper reflects the European perception of hemp both as a necessity for trade and as an item of value for economic and political spheres alike:
When our absolute dependence on Russia for this essential article is considered, and combined with the fluctuating state of politics in Europe, it is surely a wise policy to relieve ourselves, by every possible resource, from a dependence on foreign nations for Hemp.11
1. Observations on the sunn hemp of Bengal: with statements of experiments made from 1802 to 1806 to ascertain its comparative strength with Russian hemp, and the advantages of encouraging its culture and importation: to which added sundry remarks and suggestions calculated to assist the endeavours of the residents in India towards its improvement, and to remove the unwarranted prejudices excited against it (London: Lane, Darling, and Co., 1808), p. 14.
2. Richard M. Klein, The Green World: An Introduction to Plants and People (New York: Harper and Row, 1979), p. 161.
3. Klein, pp. 366-367. For hemp as funeral garments, see Cyril Birch, Stories from a Ming Collection: Translations of Chinese Short Stories Published in the Seventeenth Century (New York: Grove Press, 1958), pp. 144-145: "When he heard all this, Chung-hsiang wept endless tears of remorse. He put on the sackcloth of mourning, and with a girdle of white hemp about his waist and a staff in his hand, entered the grounds of the monastery and wailed and mourned before the grave."
4. Klein, p. 366.
5. Alfred W. Crosby, Jr., America, Russia, Hemp and Napoleon: American Trade with the Baltic, 1783-1812 (Columbus: Ohio State University Press, 1965), pp. 19-22.
6. Crosby, p. 20. Crosby also mentions that this was of little concern at the time, since dew-retted hemp was used to make rope to bind cotton bales. The stronger, Russian water-retted hemp (see below) was more valuable for making cordage and rope for overseas voyages.
7. Crosby, pp. 20-21. Note on p. 21, for example, Crosby's description of how hemp was lovingly handled and prepared by the Russians in the nineteenth century: "Even in drying immediately after harvesting the stalks were not permitted to lie on the ground but were hung on racks. After two days, unless the weather was warm enough to dry the stalks with no artificial help, the stalks were placed in a kiln. In either case, after three days the stalks were placed to rest or steep in a stream or pond, with weighted frames on top to insure that they would stay completely immersed. The clearer the water, the brighter and silkier would be the hemp. After sufficient retting--about three weeks in warm water and five weeks or more in cold--the hemp was taken out and dried for no less than two weeks, followed by twenty-four hours in the kiln, or for as long as a whole winter, depending on the kind of finished product desired. Then the stalks were broken on a hand-mill, the husk beaten off, and the remainder drawn through a wooden comb to unravel the fibers. The hemp was then stored in sheds, ready to be sorted."
8. See Klein, pp. 161-164, for the historical progression of the spread of Cannabis sativa.
9. We see the case of Russia above. In a 1722 compilation of several treatises, The Several Acts for the Improvement of the Hempen and Flaxen Manufactures in this Kingdom (Dublin: Andrew Crooke, 1722), it is mentioned that, in order to spur the growth of hemp in the British Isles, merchants who imported "good, sound Foreign Hemp-seed into this kingdom...of the Growth of Russia, Germany, the Netherlands, and the East-Country...shall receive for every Hogshead of such Hemp-seed as a Praemium, the Sum of Five Shillings Sterl." (pp. 14-15).
10. Klein, pp. 366-367: "Both Virginia and Kentucky were deeply committed to the cultivation of hemp; in 1762, Virginia gave cash grants to hemp planters and fined those who would not grow the plant...Hemp was a major industry in Kentucky, especially in Fayette and Bourbon counties."
11. Observations on the sunn hemp of Bengal, p. 19.
Trade product essays have been contributed by graduate and advanced undergraduate students in the Bell Library’s Expansion of Europe seminar (Hist 5962), unless otherwise indicated. Essays without author attribution were contributed by staff. For information on the Expansion of Europe seminar, contact the curator at firstname.lastname@example.org.