The H. Adrian Smith Collection at Brown University. From their web site: https://library.brown.edu/collatoz/info.php?id=104
The H. Adrian Smith Collection of Conjuring and Magicana, long considered one of the finest private libraries on conjuring and magic, includes 16th century titles on natural magic, alchemy, astrology, religious rites, and witchcraft. Later holdings include sections on conjuring, card tricks and games, magicians as performers, magic periodicals and other works intended for practicing magicians, posters, ephemera, and realia. The Collection is the gift and bequest of the collector, class of 1930, who as an undergraduate put himself through Brown by giving magic performances.
Even though it says "private libar[y]", it is not in private hands, and I believe that it can be viewed with appointment.