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

Figure 1. Cannabis sativa.

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.

Figure 2. A group of merchants examine hemp fibers as they are being unloaded at port. (From Traité de la Fabrique des Manoeuvres pour les vaisseaux, 27.

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:

Figure 3. A group of eighteenth-century philosophes thoroughly examine C. sativa. A young servant brings two huge stalks of bound hemp for further experimentation. (From Traité de la Fabrique des Manoeuvres pour les vaisseaus, 1)