The Fever Tree (2)
It can be fairly argued that along with Jared Diamond’s Guns, Germs and Steel cinchona bark, valued for its medicinal properties in the treatment of malaria, played a major role in the successful colonisation of countries by the imperial powers. It reduced the mortality rates amongst troops and administrators, allowing them to maintain a permanent presence in areas where previously they had struggled to survive.
By 1768 cinchona bark was being used as a prophylactic, James Lind, a British naval surgeon, recommending that as long as a ship lay at anchor in a tropical port “every man receive a daily ration of cinchona powder”. The increase in demand led to supply issues with trees being felled in indigenous regions in industrial quantities and prices rising, Lack of experience of the bark, uneven qualities of the consignments and the deliberate contamination of the bark with barks of other tress compounded the problems.
Nevertheless, powdered cinchona bark “administered in various forms and in various vehicles remained the main anti-malarial agent until 1820”, when, according to Kew, the first quinine alkaloids were extracted and described by Pierre Pelletier and Joseph Caventou, becoming within five years the standard treatment for malaria.
With the supply of the requisite raw material continuing to be in short supply and prices on the increase, the Dutch in 1852, and the British, under the leadership of Sir Clements Markham in 1860, sent expeditions to South America to secure supplies of cinchona seeds and plants to grow in their colonies. An obvious solution, but they proved tricky to grow.
They do not like frost, trees preferring a cool climate where there is little contrast between summer and winter and day and night temperatures, preferring a rich soil and unable to bear stagnant moisture on their roots, direct sunlight, or flat land. In Madras seed beds were protected by layers of fern, sufficiently thick to shade the ground. They also, according to T C Owen in his Cinchona Planter’s Manual (1881), had the “extraordinary habit of sporting or hybridising…most marked in the finest species”. On top of all that, only three of the 65 species of the genus Cinchona produced sufficient alkaloid to be worth cultivating.
Nevertheless, between 1854 and 1864 cinchona trees were introduced into India and Java and experiments were conducted in growing in various outposts of the British Empire, including Burma, Sri Lanka, Malaya, the Sudan, Jamaica, Trinidad, St Helena, Mauritius, Australia, and New Zealand. However, according to an article in Nature, published on December 7th 1929, the principal source of cinchona from the British Empire was from government-owned estates in India, principally in “the Nilghiris in the south, in the Darjiling district in Bengal (perhaps the best known) and…in Burma”. There were also quinine factories in the Bengal and Madras Provinces.
The widespread uprooting of cinchona trees to obtain bark was phased out after 1863 when a Mr McIver discovered that “if a portion of the bark of a living cinchona be carefully removed so as not to injure the young wood of the tree the removed bark will, provided certain precautions are taken, gradually be renewed.” Moreover, the renewed bark which grew back over three years was richer in alkaloids than the original. This process would then be repeated every three years until the tree died naturally or was too old to renew its bark.
