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No. 518:
Slaves and Smallpox

Today, African servants teach medicine to Colonial America. The University of Houston's College of Engineering presents this series about the machines that make our civilization run, and the people whose ingenuity created them.

We know Cotton Mather as a famous preacher in Colonial Boston. We hear much less about his interest in science and medicine. Yet he pressed the case for smallpox inoculation long before 19th-century science understood it.

Mather preached a sermon in 1712. He said:

... the Practice of ... preventing ... Smallpox [by] Inoculation has [not] been introduced into our nation, where ... so many ... would give Great Sums, to have their Lives insur'd from the dangers of this dreadful Distemper. ... I cannot but move that it be WARILY proceeded in.

That year, a ship had reached Boston from Barbados. It had one case of smallpox on board. Soon, an epidemic swept the city. It wasn't the first. Years before, smallpox almost killed three of Mather's children. He cared deeply about fighting it. But where did he learn about inoculation?

He'd seen it first hand in his African servant. The man showed Mather his smallpox scar and told him that you

... take the Juice of the Small Pox, and Cut the Skin and put in a drop: then by 'nd by a little Sick, then a few Small Pox; and no body dye of it; no body have Small Pox any more.

Boston ignored Mather until one physician began doing inoculations. That unleashed a firestorm. One man asked if we should trust patients to the "groundless Contrivances of Men" instead of the "all-wise providence of God Almighty." Another threw a bomb through Mather's window. It didn't go off, so Mather got to read the note on it. It said, "... you Dog, Dam you, I'l inoculate you with this ..."

A 15-year-old printer named Ben Franklin was working on his older brother's newpaper. They also took up the case against Mather. But inoculation went on. After, all, when you look down the barrel at death, you take some chances to preserve life.

By the time the epidemic had passed, smallpox had hit half the population. It killed one in twelve. Doctors had inoculated only 300 people. The treatment killed one in fifty of them, but none caught the disease again. The people who'd gambled on crude inoculation did twice as well as the rest. They did four times better than the ones who'd been sick.

So, by the time science okayed inoculation, New England had seen it working for more than a century. In America, we were prepared to take up this strange practice.

In 1721 we knew people who had used inoculation for a long, long time. We learned it from African slaves -- from a far more advanced people than we thought. We learned it from an old civilization that we still know too little about, even today.

I'm John Lienhard, at the University of Houston, where we're interested in the way inventive minds work.

(Theme music)

Rudolph, R. and Musher, D.M., Inoculation in the Boston Smallpox Epidemic of 1721. Archives of Internal Medicine, Vol. 115, June 1965, pp. 692-696.

Mather also read European accounts of inoculation, but only after he'd learned of it from his servant. It seems that personal experience with inoculated Africans was the most powerful driver of Mather's enthusiasm. Mather acquired the servant four years after his children had barely survived smallpox. The servant's name was Onesimus.