[Blackstone] Johnstone, George. Important TLS Explaining Blackstone?s Floating Light Bulb. Dated August 5, 1975, Johnstone, who served as an assistant on Blackstone Sr.?s show, writes to British illusionist Jeffrey Atkins describing how Blackstone presented the effect, and in particular explaining ?the handling while going down into the audience? and other fine points. The verso of the sheet features several drawings in blue ink, and a nearly-complete explanation of the effect in Johnstone?s hand. One 4to letterhead sheet, folded from mailing.The Floating Light Bulb was, both in the hands of Harry Blackstone Sr. and Jr., a masterpiece of showmanship, magic, and personality that became a family trademark. Johnstone?s letter illuminates the backstage and onstage working of the feat from a unique perspective: that of someone who helped make it happen. While simple, his drawings make clear Blackstone?s behind the scenes setup, the onstage mise-en-sc?ne, and call out weak points in the presentation. The body of the letter, though brief, outlines details that only someone in the company of the master could know and glean from firsthand experience. A complete explanation of Blackstone?s trick has never been published.