I just found the following information online. I'm now seeing Sir Thomas in a whole new light. It seems certain that if he had sugar plantations in Antigua, then he was a slave-owner. The plantations were run as 'machines' and the slaves were the necessary cogs which kept that machine going. The following harrowing account shows with terrifying clarity, just how the plantations were run:

The sugar industry was a messy business. Planters, clearing huge tracts of forested land, devastated the environment. In 1690, trees covered more than two thirds of the British colony of Antigua. By 1751 planters had stripped every acre suitable for cultivation. Antiguan John Luffman, writing in 1786, observed that even the largest hills were "clothed with the luxuriant verdure of the sugar cane to their very summits." The rapid deforestation only heightened the region’s propensity for drought and erosion.

It was also extremely lucrative. In the 18th century, Antigua rivaled Barbados as one of the leading producers in the Caribbean, although neither could compete with Jamaica or French Saint Dominigue (Haiti). "Barbados, in one period, and Antigua, in another, were producing more wealth than the entire North American continent," says Conrad Goodwin, an anthropologist who (along with geography Lydia Pulsipher) has spent more than a decade excavating and studying sugar plantations on Antigua and the neighboring island of Montserrat.

The production of sugar—from holing, planting and harvesting to crushing, boiling and curing—depended on a large work force. To meet the demand for labor, Antiguan planters imported tens of thousands of slaves from Africa. In 1678 there were 2,308 whites and 2,172 blacks on the island. By the mid-18th century, Antigua’s population had grown to nearly 40,000, and blacks outnumbered whites 10 to 1. David Barry Gaspar, an historian at Duke University, speculates that the ratio of blacks to whites would have been even higher if thousands hadn’t committed suicide or died as the result of accidents, disease, poor diet, hard labor and mistreatment at the hands of their masters. "Because of the general oppressive environment of slavery, the slave population was not self-reproducing," says Gaspar. Their ranks had to be constantly replenished with imports from Africa.

A slave’s life was grim beyond our capacity to imagine and sometimes beyond their capacity to endure. The workday was endless, and beatings were common for the smallest infraction. Mary Prince, a slave who lived on a number of different Caribbean islands in the early 19th century, describes her treatment by one particularly cruel owner: "To strip me naked—to hang me up by the wrists an lay my flesh open with the cow-skin, was an ordinary punishment for even a slight offence."

The conditions on plantations drove some slaves to suicide and infanticide. Others fought back with insubordination, malingering and feigned illnesses. Running away was virtually impossible since by the mid-18th century the forests had been cleared and most of the smaller islands afforded no place to hide. But, as recent scholars have begun to see, the slaves were often resourceful in adapting to their plight. "I’m not saying that slavery wasn’t bad, because it was," says Pulsipher. "But slaves were not just victims. We should give them credit for being able to seize a bad situation and make the best of it."

On most plantations slaves managed to carve out a degree of autonomy by insisting on certain rights, such as a weekly day off and the right to sell, at Sunday market, food they had grown in their own gardens. "One of the forms of both accommodation and resistance, especially on Montserrat, was through these slave gardens up in the hills," says Goodwin. "Because they could escape white eyes, these gardens had connotations of freedom and self-worth. But the gardens were also advantageous to slave owners because they relieved them of some of the responsibility of supplying food to slaves."

In other parts of the Caribbean, however, slaves were not so fortunate. On Antigua, slaves had trouble finding space to plant their gardens because nearly every acre was in cane. Despite laws ordering slave owners to provide plantations with provision grounds, many wouldn’t spare the land to ensure that slaves were adequately fed.

Throughout the Caribbean, sugar plantations were a curious blend of farming and factory work because so much of the industrial processing of the sugar was carried out on the spot. Mintz has dubbed the plantations "precocious cases of industrialization," and even the planters themselves recognized their industrial elements. In "An Essay Upon Plantership," Samuel Martin, an Antiguan planter writing in 1773, described the plantation as a machine with many moving parts: if one broke, the machine broke. "Even that early, labor was very important, filling many cogs in the machine," says Goodwin.

The "sugar" cycle began in August or September, when the laborers prepared the fields for planting. Slaves, wielding hoes under a mercilessly hot sun, dug holes about five or six inches deep and about five feet square, into which they placed cane cuttings, covered them with a layer of mold and prayed for rain. The slaves tended the new cane shoots as they grew; the crop was harvested, one field at a time, 15 months later.

When it came to the harvest, timing was everything. As soon as the sugar cane was ripe it had to be cut and ground, often within 24 hours to keep it from spoiling. Black overseers, called drivers, would stand behind a line of slaves, crack their whips and give the order to start cutting. From the break of dawn until after dusk, the slaves toiled in the hot, sticky fields—cutting the cane, gathering up the stalks, stripping off the leaves and loading the 100-pound bundles onto ox carts bound for the mill. The pace was so frenzied that pregnant women were sometimes obliged to give birth in the field and then continue working.

For the slaves who fed the mill, the work was less physically demanding but posed different dangers. The feeders, as they were called, were liable, especially when tired, to get their fingers caught between the vertical rollers that crushed the cane. A watchman stood ready with a hatchet to sever an arm before it could be drawn into the machine. As terrible as this must have been, the alternative was worse. The rollers couldn’t be stopped by flipping a switch. "If the limb wasn’t chopped off, the slave would be crushed to death," says Goodwin.

The boilermen had a less exacting but hotter and heavier task. Juice from the sugar cane would enter the boiling house by a pipe that ran from the mill, and workers would siphon it into a great copper basin. After several hours of boiling and skimming, the slaves would ladle the steamy liquid into a number of successively smaller coppers until it was ready to crystallize. The sugar was then cooled, packed into barrels and rolled into the curing room. Holes were drilled in the bottoms of the barrels, allowing the molasses to drain into separate containers.

Laboring in temperatures above 100 degrees, the boilermen often worked through the night, and the darkness increased the likelihood of serious burns from the scalding, sugary liquid. But because their job required a high degree of knowledge and skill, the boilermen were among the most valued slaves on the plantation.

Slaves used the molasses and skimmings from the boiling house to make rum. Water, molasses, yeast and lees were combined in a fermenting cistern and left for a week to 10 days. The fermented liquid was distilled into rum and decanted in wooden barrels. The rum, as well as sugar and molasses, was stored in a warehouse until a ship arrived to carry it either to Europe or to one of the North American colonies.