Sir William Crookes

Does anyone have any decent material on Sir William Crookes's investigations of mediumship? I found the name on a pop news site listing ten afterlife experiments, but all it said was that Crookes took care to make sure all sittings happened in his house, and that he chose the guests. Wikipedia was unhelpful; not so much due to the skeptical edits (which are still an ongoing issue, BTW; one editor has been responsible for nearly every edit made to a parapsych page this year) as that there aren't decent links as citations. I was curious in learning more about the guy.