1966/1960 mention of 20-sided dice

[Malchor]

U.S. Navy Fundamentals of War Gaming by Francis J. McHugh

Chapter 1-2 were printed in Feb. 1960 as A Manual of War Games, Chapters 1-5 were published in Nov. 1960 as the first edition. The second edition was retitled Fundamentals of War Gaming and published in Nov. 1961. 3rd edition has general revisions in 1966. So, unfortunately, it is hard to tell which edition first had the following.

www.dtic.mil/dtic/tr/fulltext/u2/686108.pdf

Two interesting bits: 

1. The use of 20-sided dice, see p. 3-20 mentions and p A-3 for more detail. 

2. A table for using six-sided dice for percentile rolls, like the one found in Michael F Corns game Appendix A, Chance Devices, pages A-1 and A-2.

There are reprints around if some other pages are too hard to read (e.g., books.google.com/books?id=V32TYh81w-gC&printsec=frontcover&dq=Fundamentals+of+War+gaming&hl=en&sa=X&ved=0ahUKEwjO7u-s45jeAhWBhOAKHdPqDKoQ6AEIKTAA#v=onepage&q=Fundamentals%20of%20War%20gaming&f=false)

Wondering if Michael Korns or Dave Wesely had access to this book.


See also: US Army use of 20-sided and 12-sided dice in 1922

[geoffrey]

[Malchor]

A little follow up on the Jampese d20s. Hopefully something here is new.

Looks like these started being available in the 1950s.

The Japanese Standard Association sold the Random Number Generating Icosahedron Dice in the 50s and 60s.

The inventior is said to be Yasushi Ishida and patented by Tokyo-Shibaura Electric Company.

I went to a talk on Lean Product management using Monte Carlo simulations. We used d10s. My guess is this, or something similar was what the dice were meant for.

Lean is the American name for a Japanese business philosophy and set of methods and tools that were brought to Japan by an American statistician named Deming to help rebuild Japan after the war. The Deming awards are still a thing in Japan. So 1-10 random generators to run Monte Carlo simulations makes total sense, the need was there in the 1950s.

20facesoffate.com/throwback-thursday-the-oldest-modern-d20/

[Stormcrow]

It's not surprising that twenty-sided dice existed long before D&D, since the twenty-sided die is simply a regular icosahedron, one of the five platonic solids.

I was going to say I'd be more impressed with the pentagonal trapezohedron if it were used as a (10-sided) die prior to D&D, but then I came across this on Wikipedia: "The pentagonal trapezohedron was patented for use as a gaming die (i.e. "game apparatus") in 1906. [U.S. Patent 809,293]."

Hey look, a page dedicated to listing dice patents!

[Malchor]

It is not so much the d20, as a few examples of the shape being used as a die since ancient times exist.

It is just that the Japanese 0-9 twice 20 sided die existed in the 1950s. These die specifically enfluenve military wargames, the recreational wargames and finally RPGs.

As far as 0-9 twice 20 sliders, these are the earliest, unless (or until) someone finds something earlier.

[Malchor]

That said. This kind of blew my mind.

A US patent files in 1963, granted in 1965 for a d4, d6, d8, d12 and a true d20: freepatentsonline.com/3208754.pdf

Files by Fredda F. S. Sieve of New York City for a game.