I'd written once before, just a little, on De Laurence and his influential Great Book of Magical Art and Hindu Magic (aka The Obeah Bible.) It's interesting to see early uses of common hoodoo ingredients, like when I found 17th century references to lodestone and swallow's heart love spells in Wecker. De Laurence -- plagiarizing from The Magus, which was itself plagiarizing from earlier sources -- brings up the first mention I've seen of black cat and black dog hair for a breakup spell, in the following:
...for divorce and separation of the man from the woman, make a seal of red copper, being the image of a dog biting his tail; and then perfume it [id est, smoke it in an incense] with the hair of a black dog and a black cat.Interestingly, some of these "seals" that De Laurence/Barret describes in the Great Book, I've seen described elsewhere as being more like poppets or voodoo dolls (in this case, a copper state of a dog biting its tail.) I'm unsure which method is more correct; though for this case it's probably easier to engrave a copper seal than to cast a statue.
Additionally, it is mentioned elsewhere in the book that one should write out (for that particular spell above) the symbols and names of the spirits of the moon, which it includes on graphs elsewhere.
De Laurence and his books were so influential that in some regions, casting a magic spell on a person is called 'De Laurencing.' In fact, the association with Obeah and Voodoo practice has fixed it so that to this day, De Laurence's books are banned in Jamaica.
Despite certain negative reviews left for the facsimile edition of the Great Book, it actually is more than just a ripoff reprinting of The Magus. Somewhere around halfway in, Book Two of "Hindoo Magic" (which unlike part one does occasionally have something legitimate to do with Hindu practices, like its section on yoga, prana and breathing techniques) does appear to be legitimately written by De Laurence. He gives tons of magic spells using some kind of Temple Incense that he used to sell (Rev. Jim at COGL tells me it was made from patchouli and sandalwood) -- henbane and Temple incense produces visions of apparitions, sulfur and Temple Incense drives away evil spirits, burning Temple Incense every Tuesday in your rooms keeps you holy and powerful, so on and so on.
It's got lots of other things that were probably new information at the time (or at least the first widely distributed printing) like guides to color therapy and use of colors in magic, a guide to how to tell if your dreams are ominous or not, and the said breathing methods, a lot of which is a part of modern magical practices. Sometimes things said by Hyatt's informants make more sense in light of reading De Laurence's book.
While the writing can be a little dull -- since it's quite old-fashioned -- it's definitely a worthwhile thing to check out if you're interested in "old style conjure" or voodoo.