A Web site called Drinking Cup has a very interesting article about a liquor smuggler nicknamed 'The Real McCoy' (from his surname) who was active during Prohibition. It gives a lot more background about where the liquor came from and how it was carried to the USA. Here's an excerpt.
Recognising the potential for legal trade just outside Americas three mile marine border, Bill's risk free technique was to park his fully laden vessels just inside international waters and arrange for mainlanders to make their way through Rum Row to purchase liquor from his floating stores. Always a prudent man, only two potential buyers were allowed aboard at any one time and all trading vessels would be under the scrutiny of a swivel machine gun on the yachts prow to deter any idea of hijacking or argument. Despite the security measures, Bill's reputation and success continued to grow and soon loyal customers were even invited to remain aboard for evening cocktails.
Not just credited with inventing the technique known as Rum Row, Bill is also said to have developed the smugglers ham or burlock (aka sacks by the US Coast Guard), a more convenient form of moving and transporting liquor between vessels. A ham consisted of a pyramid stack of 6 bottles (stacked 3,2,1) wrapped tightly in straw and burlap (hessian sacking). These bundles could be easily stacked top to tail and were quicker and safer to move between vessels than the standard wooden cases of 12. Some hams were even stuffed with salt which, if about to be boarded by authorities, could be thrown overboard where they would sink with the weight of the salt hiding any incriminating evidence. Later the salt would dissolve with the sack floating back to the surface for collection once again.
. . .
Potentially the biggest influence of all was the impact Bill made on a sleepy French fishing community on the island of St Pierre just south of Newfoundland, Canada. Recognising potential in its location to the US mainland, Bill officially moved his operation from Nassau to the island in 1922. Located just 970 miles from the Rum Row of New York city, St Pierre also had the solid advantage of being a French colony (and therefore outside of US law ), offering a port that didn’t freeze over in winter, no competing factions, total cooperation from the poor locals and low export tax on all products shipped. What would follow would single handily transform the islands community and economy into one of the most successful smuggling ports in history.
A year after Bill first arrived with a hold full of Canadian Club whiskey, over 1000 vessels would be recorded having come and gone from the small island. Initially a fishing port with a population of 4000, St Pierre was transformed commercial merchant town. Fishing docks were converted into negociants, fisherman rehired as longshoreman or crew aboard runners and almost every spare barn, garage or cellar converted into a liquor warehouse. By the end of 1923, 6 million bottles would be recorded passing through the town, an equal of 1500 bottles per every man women and child on the island. This period St Pierre’s history has become known as Le Temps de la Fraude – “The time of the scam”. A visiting Canadian journalist wrote of the town, “The odour grew so strong that at times the fog that rolled up St Pierre’s steeply inclined streets with the nightly tide would carry a distinct Scotch flavor”.
There's lots more at the link, and at other articles linked in the original. I found it a fun and informative perspective on history. Recommended reading.