IIRC, the working of "Multum in Parvo" (the effect where a glass of milk is poured into glasses of four different sizes, each time filling each glass completely) was originally published in a magic magazine. Can anyone confirm that memory and perhaps cite the actual magazine issue (month and year) that it appeared in?
(I think I read that fact about "Multum in Parvo" in one of Will Dexter's books--perhaps _Everybody's Book of Magic_ in the chapter about magic magazines.)

I would also be interested in learning about any other marketed effects that were first written up and explained in a magic magazine.

Thanks!

----- Amado "Sonny" Narvaez

Benson Dulay's Multum in Parvo is in The Magic Wand Vol. 35 No. 212 December, 1946 , edited by George Armstrong, on page 152 - 153.

It is also in The Magic Wand Year Book by George Armstrong 1947-1948.

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