Life has obliged him to remember so much useful knowledge that he has lost not only his history, but his whole original cargo of useless knowledge; history, languages, literatures, the higher mathematics, or what you will – are all gone.

In the early 1800s, both Spain and Portugal disseminated the smallpox vaccine throughout the Americas via the ‘arm to arm of the blacks,’ that is, enslaved Africans and African-Americans, often children, who were being moved along slave routes as cargo from one city to another to be sold.