Pontifications on Poison
Being some ramblings on events associated with poisonous plants.
Thursday 15th December 2011
The one thing you can say about our species is that we are meticulous about the way we approach doing ourselves considerable harm. I thought I’d return to the archives of the Royal Society’s Philosophical Transactions following previous visits on 27th October, 30th October, 5th November and 15th November.
I found two pieces about the production of tobacco that reminded me of what a former tobacco farmer from Rhodesia had told me about growing Nicotiana tabacum for sale.
The first was a 1676 description of Virginia provided by Mr Thomas Glover, ‘an ingenious chirurgion [surgeon] that hath lived some years in that country’. Mr Glover goes to great lengths to try and describe the physical geography of Virginia to an audience that would have no information about it and he spends some time explaining the habits of the ‘Indians’. He notes that their numbers have decreased markedly but attributes this to in-fighting between different ‘towns’ rather than to the arrival of European settlers.
He then goes on to detail the care with which tobacco is grown. How the seeds are sown in trays and planted out into carefully prepared ground. How the top is pinched out of the plants once they reach a certain height so that all the vigour goes into the 12 to 15 leaves then on the plant. How they go around once a week to remove any side stems that are starting to form. And then how the plants are cut down, and hung up for several weeks until the leaves can be removed from the stalks without being damaged.
In 1702, a Mr Strachan reported on the production of tobacco in the Dutch colony of Zeylan on the island of Sri Lanka. The growing methods used are similar to those described by Mr Glover but Mr Strachan says that the removal of the tops is done at different times depending on how strong the grower wishes his tobacco to be. He says that plants grown to produce only 10 to 12 leaves are stronger than those left to grow 18 to 20 leaves before the top is pinched out. He notes that breaking off of side stems is done every 3 or 4 days rather than weekly. The harvesting and preparation for sale is very similar to Mr Glover’s description of the process but Mr Strachan says there is a second sort of tobacco plant that is left to grow as it will and then cut down and piled in a heap to mature. This tobacco, presumably cheaper, is favoured by the Dutch soldiers.
Both descriptions show that, even in the 17th century growers had discovered how to manipulate the plant to obtain both a higher yield and the required quality.
The Rhodesian farmer who told me about how he grew tobacco showed that this manipulation had become even more refined by the mid-20th century. He explained that his plants were harvested by having individual leaves removed rather than cutting the whole plant. I don’t remember the names he gave them but he said that each layer of leaves had different qualities and would be used for different purposes. Thus, some leaves were ideally suited to wrapping cigars, others shredded quite coarsely and were used for pipe tobacco with others giving the fine shred required for cigarettes.
On his farm, harvesting was done by hand so the real skill was to get every plant to the same height so that the farm labourers could easily go through a field picking all the leaves from the same level thus producing the highest quality products.
One of the stories that we sometimes told when talking about Nicotiana sylvestris was that, when tobacco was first brought from America, sailors would tie leaves to their bodies to smuggle them but would die from absorbing the nicotine when sweating on the voyage home. In fact, Peter Macinnis in ‘Poisons - from Hemlock to Botox and the Killer Bean of Calabar’ says there was just one case, in the nineteenth century, of such poisoning but says that, in 1970, problems caused by tobacco pickers in North Carolina putting picked leaves under their arms were first identified as an industrial disease.
One of the frustrations of working in the Poison Garden was that there was never enough time to get every detail of visitors’ stories or experience. This meant I wasn’t able to find out from the Rhodesian tobacco farmer whether his farm labourers experienced any problems from constantly handling the leaves during harvesting.