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Error in magic chapter in Visual Explanations?

This has nothing to do with information design, but I thought I'd point out what appears to be an error in your description of the 'Downs Eureka Pass' sleight of hand.

Briefly (for those who don't have the book): a magician with his right hand makes a coin seem to vanish while in fact concealing it behind his fingers. The left hand then openly transfers a second coin to the right, surreptitiously taking the first, hidden one in the process. The right hand then 'vanishes' the second coin in the same manner as the first, and the cycle can repeat.

ET writes: "Since the left hand must hide an increasing accumulation of potentially clinking coins, the repeated cycles grow more difficult."

Surely, only two coins are required, and neither hand ever holds more than one. The 'vanished' one becomes, moments later, the next 'new' one apparently drawn from a nonexistent supply in a pocket or other container.

The 'reverse' of this effect is to make coins 'appear' in the right hand by essentially the same technique. The left hand in taking the coin loads a second one into the concealed position, so another coin can appear in the right moments later. Usually the magician will with his left hand pretend to drop the just- appeared coin into a metallic pail, which emits a nice loud 'clink' to signal that the coin has hit the bottom. In fact, there's a device hidden in the pail which creates a false noise, as the magician conceals the first coin again in his left hand, for transport back to the right as the cycle repeats. The audience doesn't actually see the coins falling into the pail ("Hey, why doesn't he use a glass bowl?") but their ears get the message, and believe.

We now return you to your regularly scheduled topics...

-- John Bakke (email)

Response to Off topic: Magical error in VE book, page 68

My source for the material on the Downs' Eureka Pass is T. Nelson Downs, Modern Coin Manipulation (London, 1900), as cited in my Visual Explanations.

Downs writes about the Downs' Eureka Pass in his book on pages 81-83: "This pass is used for the vanishing of any number of coins, up to 20, one at a time. . . .Of course, considerable practice is necessary to palm the coins one after the other without noise . . ." The coins have to go somewhere, since there are many lying on the table at the start of the trick!

By the way, the non-error appears on page 56 of Visual Explanations, not on page 68 as stated in the question.

Perhaps my co-author of the magic chapter, the famous magican Jamy Ian Swiss will also comment.

-- Edward Tufte

Response to Off topic: Magical error in VE book, page 68

The question is completely understandable, and indeed a good catch, based on our incomplete excerpt. Here is the complete relevant passage, which should clarify matters. Downs' claim of "not so difficult" is questionable, as is, in fact, his claimed ability to successfully execute this with 20 coins, which seems unlikely, even for a man of Downs' remarkable skills.

Jamy Ian Swiss

THE DOWNS "EUREKA" PASS (from Modern Coin Manipulation by T. Nelson Downs)

"The author has extreme pleasure, in the following description of the pass to which he has given the above title, in taking the reader into his confidence [...] and explaining to him fully what the writer conscientiously believes to be his most novel, puzzling and prettiest feat:

The pass is used for the vanishing of any number of coins, up to 20, one at a time.

The coins are lying on the table. One is placed in the right hand is in fig.1 (in readiness for the back palm). This is made and both hands shown (apparently) empty. The left hand now picks up another coin by the first finger and thumb, and proceeds to place it on the right hand in the position occupied by the first (see fig. 28), but in the act of doing so the middle fingers of the left hand go to the back of the right and remove the first coin (see fig. 29). The left hand now leaves the second coin on the right hand, which back palms it, the left hand in the meantime palming coin No. 1.

This is repeated until the whole of the coins are palmed in the left hand.Of course, considerable practice is necessary to palm the coins one after the other without noise, but this is not so difficult if the first coin is palmed as per fig. 9, and each following one is placed under the preceding one."

[Note added by ET: Downs' Figures 28 and 29 are the ones reproduced in Visual Explanations. Please note the silver ink highlighting the coins in our version!]

-- Jamy Ian Swiss (email)

Forgive the extremely late response, but I came across this thread and just want to add a thought. Historically speaking, there is reason to believe that the very purpose of Downs book -- his first, which was sold as a souvenir to spectators who attended his shows -- was to emphasize the difficulty of the sleights, rather than teach them. Downs, whose talent with coins was legendary, distributed these books, which arguably "exposed" the very effects he was perforrming, to showcase his unusual skill. This may explain, in part, why the books explanations may, at times, been less than transparent and the choice of more difficult means of accomplishing an effect.

Gary Brown

-- Gary Brown (email)

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