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Wednesday, January 21, 2015

The Death Machine Letter Scale

                                               The Death Machine Letter Scale
                             I have just a little more work to do on this section. I found new info to help out get more precise measurements.

     Here is the Death Machine letter sent by the Zodiac killer. It is a 6 page letter and and has a schematic of a bomb. In this post I am going to scale the letter and determine the size of the pages. This could be something that someone else may find useful for something, but I am doing this to some future work I plan on doing.

                                                          Here is the letter.

Back of page six.

                    I highlighted the fold lines in these examples. I put them side by side for comparison which you will see in a minute. I also use these to help determine the scale.

             In these examples I got the scale for pages 1 and 6 from the two examples above so those two are confirmed. . I then Scaled the remaining pages 2 - 5 by lining up the fold marks on the pages from where they were folded.

           I highlighted the fold lines on the pages and matched them to each other. I then copied the scale from one page to the next. I show the whole process.

Then I highlighted the fold lines on page 5 and matched the to page 6. 

Seeing that the fold lines of the pages match I then copied the scale marker from page 6 onto page 5.

That is confirmation enough for me. This is how the whole process is going to go. 

Now I will highlight the fold lines on page 4 and match them to page 5.

Then copy the scale marker from page 5 to page 4.

Highlight the fold lines on page 3 and match them to page 4. 

Then copy the scale marker from page 4 to page 3.

                        Now highlight the fold lines on page 2 and match them to page 3.

Then copy the scale marker from page 3 to page 2. 

Page 1 was already scaled .

             Now I will try to measure these before I make my final examples. You can give a little room either way for human error if you want to. Just as long as we pretty well know the scale of the pages is all that matters (at least for my experiments).

     The measure between the center fold lines are either right on or about 3 1/2 inches. All the pages meet that measurement, so it looks good to me. ( at least I think, I will be double and triple checking all of this before I finish this post to make sure I made no mistakes). This is the hardest of all the letters to scale because they're so many pages and they are all different sizes.

                    Here are some final scaled examples with a simple one inch proof of scale.

       Here are some more scaled examples. I measured these a few different ways and checked them and rechecked them. It turns out the very first scale examples I made a while back were right on the money except for page 5. It was a little off.   I also measured the pages along with the scales to see if everything matched up. It was all right on the money.

                     One last set of examples that are clean with two different scale markers.

                      The Zodiac Killer Death Machine Bus Bomb Letter with proof of scale.

                                                Here are some side by sides.


      This will give you a good idea on how different the page sizes in the letter are. The question is why? Some of it may be due to cropping.

                              I asked someone about this and this is what they told me.

Apparently, he cut only along the length of the paper, not its width. Originally I thought that this could be so that the pages would fit in a small envelope but having measured the envelopes, I find that this is not the case, i.e., the envelopes were wide enough. Another interesting thing is that he changed the envelopes a lot; you and I might have a box of envelopes at home and simply pull one each time we need one, but the Zodiac apparently got a different envelope for many letters. I have no idea why he would do that.
         That is good useful information. Many thank to Charlie at He sent me a link with some information on this. I have been reading it . Here is a link.


           Thanks to Richard Grinnell of I have found some more information on the irregular size of the letters. I have confirmed that Zodiac did trim pieces from the paper he wrote the letters on. It is a brand Eaton Marked Paper. From what I understand he used this on all of his letters except for the letter he sent in reply to the police after he sent the 408 cipher and they requested he send another letter to prove it was indeed the real Mcoy.

       It is a very interesting article and I wish they would release more info in this. I am very interested in it . Here is a link to this article. I would recommend reading it.

   The article states that the letters are 7.25 x 10.5 inches. The 340 cipher is 7.25 x 10.5 inches. It also states the kind of paper and that the paper has been trimmed so the size could vary from page to page a little.  So I am going to check just to be sure because I want ot be as exact as I can be, I will try these measurements and check them against the known scale markers. If I need to I will make corrections as necessary. I am going to measure these a few different ways and few more times before I make any final decisions.

                                           So Lets try this whole experiment again and go through the same process as the one shown above using this new piece of information . I am leaning the original work and experiment above be cause even some of them may be just a a little off they are still close and maybe even right. So after this second scaling experiment I will compare the two and then do a final post. This is more a less a double check of the original scaling experiment.

                        Lets start with page one. We are going for 10.5 x 7.25 inches

                         Exactly !0.5 inches length but around 7.2 width. It matches the scale mark.

                                                                        Page two

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