The Inventor of the Magic Boomerang Illusion is Found

[Richard Kaufman]

Live and learn: I found this today on the Internet:
http://www.tutztutz.com/2008/02/20-amaz ... illusions/
Scroll down to number 11 and you will find that: "The Jastrow illusion is an optical illusion discovered by the American psychologist Joseph Jastrow in 1889. In this illustration, the two figures are identical, although the lower one appears to be larger."

[Max Maven]

Interestingly enough, the credits regarding most optical illusions are well established. It would seem that psychologists are more aware of the value of providing such references than are those in certain other fields...

Having said that, while Jastrow was a key player in the study of optical illusions, he is frequently given erroneous credit for a classic ambiguous figure, the duck/rabbit picture. Jastrow was probably the first to explore this (along with related images such as the Necker Cube) from a scientific stance. But, the image started out as a novelty -- source apparently unknown -- that appeared in a German humor magazine in 1892, seven years prior to Jastrow's introduction of the image to academia.

[Richard Kaufman]

Hey, haven't I seen that on a silk somewhere?
"Rabiduck" perhaps?

[Joe Pecore]

Any idea who was the first to think of performing or marketing the Jastrow/Boomerang Illusion as a magic effect?

I've done it lately using those cardboard paper holders that come on coffee cups.

[Philippe Billot]

According to Potter's Index, it's presented as an optical illusion by Goldston in Simple Conjuring Tricks (1913)

It becomes a kind of bet in 200 More Tricks You Can Do (1927) by Howard Thurston under the title Which Is Larger ?

[Joe Pecore]

I did a bit of research on Jastrow and it appears he did some experiments with Hermann and Kellar.

[opie]

Is the source for Potters Index anywhere on the internet? I have made numerous searches and cannot find it there...

opie

[Jonathan Townsend]

Have there been any studies on the dimensions of the item which most affect the percieved illusion? Same for the Pogendorf lines illusion - ??

[Philippe Billot]

Is the source for Potters Index anywhere on the internet? I have made numerous searches and cannot find it there...

opie

The Potter's Index was sold by Micky Hades but I don't know if it's still available. There are 14 volumes.

I think you can find it at Ask Alexander.

[Richard Kaufman]

The Potter Index has been out of print for many years. There were rumors of updating it, but considering what the Internet has become, there's really no reason to sell a 14 volume set of books. If it were redone (and I can't see how that's going to happen at this point--too much has come out since the early 1960s) it would be sold on CDs or DVDs.
Anyway, join the Conjuring Arts Research Center and you can get it online.

[hugmagic]

The original Potters Index was published in the Linking Ring.

I got one of the last sets Mickey Hades had. Unfortunately, even then ( 1980's) in was already out of date.

The task of updating it is daunting. There is so much published in so many places now days.

Chuck Stanfield and I kicked around how it could be done. If I did say flowers and productions. Chuck would do four ace tricks, Some else could do anyother area that interested him. It truly was a remarkable assembly of references done by one man.

I second joining the Conjuring Arts Center as it will get you the results much faster and more accurately.

Richard

[opie]

Thanks gents for the info on Potters Index....and the tip to check out Conjuring Arts Center....

opie