Magnetism as "mind over matter"
Because magnetism was still being practised in his own time, Mackay ends his account of the madness around it with a note that we've seen in his book before. Just as when he ended the section about alchemy, he states that at least some good has come of magnetism.
Mackay finishes on magnetism
Mackay's finished writing about magnetism in The Madness of Crowds, and I come to my own conclusion. Would Mackay be proud?