This from the Cowper and Newton Museum, per my inquiry.

Newton captained 3 voyages:

Aug 1750 - Oct 1751 Duke of Argyle
Jun 1752 - Aug 1753 African
Oct 1753 - Aug 1754 African

Note, he's still going strong six years after his conversion in 1748.

As for disgorging ill gotten wealth, I do not agree with Ted, and in fact am surprised to hear him say so forcefully, that it is "a ridiculous idea." Hey, you steal, feel bad about it later, give the stolen stuff back. You kidnap, murder, etc etc, make a bundle, if you feel bad about that then disgorge that profit also. Not a radical idea. Unless, of course, you aren't fully repentant, just in need of some device to feel good about yourself again, in which case platitudes will do and no need to do anything that will affect your pocketbook. In consumer law it's common to make the bad guy disgorge ill gotten gains. Sure, it's a lot to ask of Newton, but is failure to do so is informative. Again, he made money on a deadly and unspeakably cruel practice (and, yes, the slave trade was controversial in England even during his time, it was abolished the year he died) later felt bad about it but not bad enough to suffer a little in the money department. Instead he took the easy way to a clean conscience, wrote nice songs and urged other people to stop doing what he made money doing. Sorry, that's not admirable, it's hypocritical. (History is full of people who renounced evil in toto, and then went from riches to rags because of a principle they believed in. It's not like we're asking Newton to be the first.)

As for Michael's Autobahn issue, I am not sure the analogy applies. Nobody thinks driving the Autobahn says anything about your views of Hitler. By contrast, I think singers of Amazing Grace are misled about Newton's nature. So, yes, drive the Autobahn and sing Amazing Grace, but recognize the nasty stuff that went into their making. And if the public begins to view your participating in those actions as an endorsement of their creators, then maybe you should consider abstaining.

Ted, I'll try to find that investment info for you. I read it at some seemingly reputable site.