From Imperial Twilight: The Opium War and the End of China’s Last Golden Age, by Stephen R. Platt (Knopf, 2018), Kindle pp. 193-194:
Robert Bennet Forbes, John’s rosy-cheeked older brother, was a middleman in the drug trade. The Lintin he had just fitted out in Massachusetts was destined for use as a “receiving ship”—based off the southwest corner of Lintin Island, far from the reach of the authorities in Canton, he operated it as a floating warehouse for drug shipments. Foreign vessels coming in from India and elsewhere with cargoes of opium would stop first at Lintin, offload their chests of the drug onto Forbes’s ship or another in the harbor, then proceed up to the Whampoa anchorage outside Canton with their holds empty of contraband and clean for inspection. In certain “money-changing shops” in the foreign compound, their captains or supercargoes could meet with the English-speaking agents of Chinese opium wholesalers (some, but not all, of whom were Hong merchants—since the trade was illegal, the Hong merchants’ monopoly on foreign trade did not apply to opium as it did to tea). After agreeing on a price, the foreign merchants took payment for their opium, while the Chinese dealers sent their own men out to Lintin to retrieve the shipment from the holding vessel.
Robert Bennet Forbes’s job was a simple one. His cargo was not his own; he merely held it on consignment for other traders who had assumed the risk (storms, pirates, market fluctuations) of getting it to south China in the first place. Chinese smugglers took all of the responsibility for moving the drug inland and up the coast—and, eventually, for retailing it within China. They also took responsibility for bribing government officials to ensure that no inspections would be made at Lintin, or at least to make sure that such inspections would be announced well in advance. There were in fact Chinese warships stationed on the opposite side of Lintin Island from Forbes’s ship, off the island’s northeastern shore, but they were under a different county’s jurisdiction than the smuggling anchorage and generally only sailed around the island in order to collect bribes from the smugglers before returning to the northeast again. As captain of the Lintin receiving ship, Robert Bennet Forbes thus bore almost no risk at all. All he had to do was stay put and keep the opium safe, earning a commission for each chest he held. The hardest part of the job, for a young New Englander who loved to sail, was having to stay in one place all the time. For suffering that, he brought in an income that in today’s currency was worth more than $800,000 per year.
The basic fact was that the opium poppy grew very well in British India, which otherwise was a spectacularly unprofitable colonial venture (and which, without the rich profits from the Canton tea trade to offset its losses and debts, would likely have bankrupted the East India Company). European traders learned early on that there was a steady if small market for opium in China even though it was illegal there. As early as 1719 we can find the Chinese demand for the drug making an appearance in The Farther Adventures of Robinson Crusoe, Daniel Defoe’s lesser-known sequel to his novel Robinson Crusoe, where Crusoe, who was rescued from his castaway fate in the previous book, made a run from Siam to China to sell opium, “a Commodity which bears a great Price among the Chinese, and which at that Time, was very much wanted there.” Though Crusoe originally intended to sail north in China to sell it, he was advised to “put in at Macao, where we could not have fail’d of a Market for our Opium.”
There are more formal records of British traders carrying Indian opium to China by 1733, when the East India Company notified the captains of two of its ships of “the late severe laws enacted by the Emperour of China for the prohibition of Ophium,” admonishing them that “you are neither to carry, nor suffer any of it to be carry’d in your Ship to China, as you will answer the contrary to the Hon’ble Company at your peril.” Going forward, the “Honourable Company” refrained from carrying any opium on its own ships, judging that the potential loss of its aboveboard tea trade was not worth the smaller reward to be gained from drug trafficking. That did not end the matter, however, but simply made an opening for independent operators who were more willing to take on the dangers of the illegal trade.