The Ecphorizer

One Zero Zero
Gareth Penn

Issue #29 (January 1984)

Unraveling the Zodiac killer's binary clues

The mass murderer known as "the Zodiac" made his literary debut in the San Francisco Bay Area toward the end of July, 1969, with a mailing consisting of a cryptogram and cover letters sent to three different newspapers. Each of the letters was signed with a crossed circle. He used

What we have here is a mathematical picture of a copulation.

the same signature on all subsequent communications during the period 1969-1971. The [quoteright]newspapers reported (and indulged in) an orgy of speculation regarding the significance of the crossed-circle signature. It was variously identified as a "mystical symbol of the universe," a totemistic sign from some (unnamed) Oriental religion, and the crosshairs of a telescopic riflesight.

That didn't exhaust the possibilities. The same sign stood for the sun in pagan Scandinavia. It appears on every Roman Catholic church in the world to signify its consecration. It is used by astronomers to denote the planet on which we live. It is also the trademark of Benchmark paper products, not to mention a dozen other significances. In other words, the derivational approach could be used to prove that the Zodiac was a Catholic priest, an astronomer, a stationery salesman, a Viking, or a member of the National Rifle Association.

Nobody took a careful look at how the Zodiac himself used the sign. It would have proven instructive. The first place in which it appears in the Zodiac literature is the cryptogram itself, where it is used as a cipher symbol standing for the letter "D." The first place in which it appears in the cryptogram is in the word "dangertue" (for "dangerous"). The first two sentences read:

I like killing people because it is so much fun. It is more fun then killing wild game in the forrest because man is the most dangertue animal oe all...(slc, passim) [NB: the "D" of "wild" is given with another symbol.]

The "D" of "dangertue" is character number 100. The letter "D" in Morse Code (1 for dash, 0 for dot) is 100. 100 in binary notation is four. The fourth letter of the alphabet is "D." And the crossed-circle sign that stands here for "D" is a circle divided into four parts-a graphic representation of the number four. There is an interlocking circle of equivalences here that makes it clear that the value of this sign is digital, and that it is to be read as both four and one hundred, since both are spelled in conventional systems of writing numbers as "one zero zero." Changing systems, the spellings become quite different. One hundred in base-two arithmetic, for instance, is 1100100, which is identical with the Morse spelling of a man's given name.

The text of the cryptogram says nothing worth the trouble it took to decipher it. But as with other Zodiac documents, the form is more expressive than the content. The text consists of 390 letters of English followed by 18 of anagram (EBEORIETEMETHHPITI). The ratio 390:18 is the same as 130x3:130x0.14159. . . The Zodiac had claimed that the solution of the cryptogram would reveal his identity; but when it was solved, as an English text, all that was seen was the red herring, "I like killing people. . ." That diverted attention from the form, which contained the real message: the number 130pi. 130 in binary, 10000010, is identical with the Morse spelling of a woman's given name. There is a woman with that name who is married to a man whose given name is spelled, Morse to binary, as "one hundred." Their son's name is Mike, and the family name which the three of them share is identical in Morse with the base-two writing of the fraction of pi carried out to 13 places (see "Te Moriarty Salutamus," THE ECPHORIZER, November 1982).

Here are the figures drawn at the foot of the Zodiac's letter to the Chronicle of 29 January 1974, with my geometrical annotation:

As the annotation demonstrates, two of the angles expressed by these cryptic figures give the numbers one hundred and 130, joined together. All of the other angles express data consistent with this identification; and I suggest that any resemblance between the figures on the extreme left and sperm-and-egg is anything but coincidental. What we have here is a mathematical picture of a copulation. It expresses the author's identity in the sense that he was engendered by that act. The small angular figure contained within the 130 degree angle, for instance, appears to be the supplement of the radian (see "11.00100100001111110110101," THE ECPHORIZER, December 1981). If that Is so, then it expresses, in degrees and minutes, the blrthdate of the son of "130" and "one hundred."

I suggest further that the number 130 has been reduced to four by casting out nines (1 + 3 + 0) in order to impose on it the same form as the number one hundred. The binary four and base-ten one hundred are both written as "100." By this roundabout route, the author is able to express the union of the persons bearing these name/numbers with a simple digital shorthand, which can then be expressed in an even more cryptic manner, as a crossed circle. In any case, one hundred and 130 are major thematic elements of the Zodiac literature, and they occur together in a multiplicity of forms and context. The crossed-circle sign, which stands for both numbers, has the purposely ambiguous value of "one zero zero," and as such it constitutes, in the author's private convention, a 27th letter of the alphabet.

There are numerous instances in the literature where certain formulations in which the crossed circle appears give sensible results when "100" Is substituted for it. I will give on example here. In a previous contribution, I mentioned that the unsigned "Confession" letter which the Zodiac sent the press and police after murdering Cheri Jo Bates in Riverside in late 1966 is composed in 1623 letters, and that the binary 1623 (11001010111) is identical in form with the Morse spelling of MIKE O. Until November 1970, the Riverside murder was a riddle within a riddle. To the Rumplestiltskin question, "What is my name?" the Zodiac has added: "What else did I do?" But even after that question had been answered, the reason for the choice of Riverside as a murder-site remained an enigma. In the interim, the Zodiac teased his readership with sly hints about his first crime.

In a letter to the Chronicle in April 1970, the Zodiac makes a number of references to Riverside, some cryptic, some blatant, such as the coy postscript: "I hope you have fun trying to fiygure [sic] out who I killed" (i.e. Cheri Bates). A diagram accompanying the letter prominently features a car battery. It was by disconnecting her car battery and then offering her a ride home that the murderer had got his first victim into his power. This letter begins with a new, 13-character cipher, which the Zodiac claims expresses his name:

one hundred               130               suffix
    1100100            10000010           101

Since so many of the Zodiac puzzles are digital, I divided the characters in this cipher into two classes, block letters and circles, and substituted for them 1 and 0, respectively. The singular Inverted umbrella, which belongs to neither class, I read as a break (-) between groups. The resulting sequence can be redivided this way:

[see Note below]

"100" Is the digital value of the crossed-circle sign, which the Zodiac used as a signature. "100" is therefore his identity. It is interchangeable, then, with the first person singular pronoun, "I." With that substitution, the digital solution of this cipher gives the same reading as the invisible signature on the "Confession" letter from Riverside: MIKE O. The use of "100" for "F" is undoubtedly dictated by considerations of security, as a backstop against the possibility that someone with more imagination than the police might attempt a digital approach, in accordance with the principle: maximum audacity consistent with personal safety.

Why did the murderer stop with the initial "O"? If the rest of his name were spelled in, let's say, ten Morse digits, then the number of letters required to spell it out digitally would have been MIKE O (1623) x (2 to the 10th power); the one-page "Confession" letter would have had to be expanded to over a thousand pages. He had a more precise and economical means of identifying himself in number, anyway. The person whose mother's name is "130" and whose father's name is "one hundred" and whose family name is given by the fraction of pi has a Social Security number which, when read as angular measurement, gives the longitude of Riverside, California.

[line width="30%"]Note about the misleading graphic above:

As is our practice, we've uploaded the print version of The Ecphorizer as it was printed, including any gross errors.

One effect is that the graphic insert to the left is the wrong series of characters and Gareth's resulting decoding into binary representation.  Back when that error occurred, Gareth sent a note of correction to The Ecphorizer, which was printed in the next issue.  We invite readers to jump to Gareth's note of correction (and the correct graphic, which is too big to insert in this space) by using this link

With the apparent aim of broadening his intellectual horizons, Gareth penn recently send out ex-editor a subscription to Duck Unlimited magazine.  This publication promotes waterfowl "management" by telling you how to shoot them.  Last month's issue included an article on how to quack convincingly.  We love it.

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