Black Magic is Not a Myth in Articles by Aleister Crowley.

“My most memorable personal experience of the effects of black magic occurred when I was living in Scotland. The machinations of a degraded and outcast member of the Order caused my hounds to die, my servants to become insane. The struggle lasted until the recoil of the current of hated caused the luckless sorcerer to collapse.” [via, also]

Consider also:

  1. “It is like looking for an escape of gas with a lighted candle. As far as the search goes, there is little fear of failure!”
  2. “They had curious effects on the neighbourhood. Part of the main road from Inverness to Fort Augustus ran through my estate. Soon superstitions about the road made the natives avoid it. People refused to use it after nightfall. Even the tough, hard-drinking workmen from Glasgow who were employed at Foyers would go a long way round to avoid that uncanny road.”
  3. “But the first call: 1896. In a Bierhalle under the shadow of the Matterhorn I met an alchemist. He is one of the best-known technical chemists in London. One of his scientific feats was the ‘fixing’ of mercury (i.e. the making of it solid at ordinary temperatures) and he had done this by the despised alchemical processes of the Middle Ages.”
  4. “In the congregational form of the Black Mass the priest, having finished his abominations–these are, quite frankly, indescribable–scatters the fragments of the Host on the floor, and the assistants scramble for the soiled fragments, the possession of which, they believe, will allow them to work their petty and malicious designs.”
  5. “Later, when I was transferring my apparatus to my house in Scotland, I employed two workmen to remove the mirrors. As they were working they were suddenly overcome, knocked out by unseen assailants. It took several hours to revive them. People passing the doorway suddenly fell down in fits. That flat remained without a tenant for years after I had left it. All this was because I had not enough experience to control the forces.”