Zodiackillersite.com

Pre dates rather substantially but:

Thanks for finding and posting these, Simplicity. Nice to see them. Another bit of Rincon history.

From the dates, these were both in the decade leading up to the introduction of mechanised mail processing and the Pitney-Bowes face-cancellers. Given the dates, however, it's interesting that they say 'Rincon Annex' specifically and don't give use the then-in-operation two-digit zone codes which - according to the modern Zip, which X posted earlier - would likely have been '05' or just '5'.

brubaker wrote:Just chiming in to say that the person who wrote the article linked below might be able to answer some of your questions. Although it looks like he didn't work at Rincon, he had a 40-year career with the USPS in San Francisco starting in 1966 and seems to be interested in postal history.

http://www.sfcityguides.org/public_guid ... 2=&topic=B

I should have paid a little more attention when reading this article, as it provides a key bit of information that pretty much goes to answer the first of our key questions.

When we began looking at where the Sectional Centre Facility might have been in 1969/70, we were looking for a predecessor to the current operation at 1300 Evans, India Basin. We had discovered that there must have been a predecessor site, as even the land on which the Evans plant is located at India Bay wasn't around in 1970, until after subsequent reclamation from the salt marshes.

Re-reading Deutche's article, I now notice it clearly written:

Peter H. Deutsch wrote:In 1983, when the Post Office moved from Rincon Annex on Spear and Mission to its present 34-acre processing facility at India Basin,...

So, there you go.

Are we certain that these letters could not have received a Sunday postmark some other way? Besides Rincon Annex?

I want to be sure we have exhausted every option before we focus all of our energy on this avenue.

Not wanting to demotivate anyone or diminish anyone’s work but i think that there is a chasm of possibilities that will eventually engulf the very logical notion that’s in play.

Chaucer wrote:Are we certain that these letters could not have received a Sunday postmark some other way? Besides Rincon Annex?

I want to be sure we have exhausted every option before we focus all of our energy on this avenue.

I would say that we’re still short of absolute certainly at this point, Chaucer. There are still a number of crucial questions that we are currently looking to have answered by (hopefully) some retired SF postal worker of the day that may help to get us there (or, equally, blow the whole thing out of the water).

That said, and given that your question refers specifically to the two Sunday postmarks, the simple fact of the local Post Offices not having been open on Sundays seems to argue strongly, at this point, against Sunday postmarks having been received at any other location than through the Sunday mail processing at the SCF. Even were this confirmed, there’s still the one question of whether mail collected on a Saturday could, under some unusual circumstance, not be processed until the Sunday and thereby receive a Sunday postmark, which we need clarifying. Were this even possible, however, wouldn’t this result in Sunday ‘AM’ cancellation, not ‘PM’ as in the two Sunday letters under consideration?

What we do know with certainty at this point, from the evidence of just the small set of both the ‘authenticated’ and ‘questionable’ Zodiac letters taken together, is that both Saturday and Sunday machine-cancellations exist, in line with regular weekday operation. Out of four (‘authenticated’) weekend letters sent by Zodiac, three of these were not processed in this manner; none of the weekday letters were ever hand-cancelled.

Again, there are a number of points that we are currently seeking clarification on that will help pin this down, but so far the strong indication appears to be that the reason for this imbalance is that Zodiac changed the method of how he posted his weekend mail in these three instances. Regular mailing achieved machine-cancelled postmarks, and the same is shown to have been possible even for Saturday and Sunday. What, then, was it that was done differently?

Add to this the fact that two of the weekend letters were certainly ones we could suppose that Zodiac particularly wished not to be lost in any complex mail collection and processing - these two containing pieces of Stine’s shirt - and we begin, IMO, to see glimpses also of the possible motivation for his doing something different with these items of mail, and ‘cutting out the middle man’ would pretty much mean mailing direct at Rincon.

Clarification will hopefully come through the collected questions a few posts back, once we or someone can find the right person to put these to.

Despite my own eagerness a short while back to press on with the idea of hand-delivery at Rincon as a strong working hypotheses, I have accepted caution and feel we need to get closer to the ‘certainty’ you refer to.

I agree re: certainty. This is a good line of inquiry, and i encourage it, but until we have eliminated other possibilities, I think we need to be cautious. I was quite excited and confident about the district codes and maps and obviously that was squashed. A healthy dose of skepticism is also required here, I think.

Simplicity wrote:Not wanting to demotivate anyone or diminish anyone’s work but i think that there is a chasm of possibilities that will eventually engulf the very logical notion that’s in play.

I think that you’re right, Simplicity, in the sense that there remains—as things stand—the very real possibility that the whole line of investigation so far could end up disappearing into a chasm, with very little or nothing left to hold onto. There is still a rug to be pulled from under our feet, for sure. The way things have proceeded so far, however, strongly indicates to me that there are not many ways left by which this could happen.

Something, certainly, was done differently in processing the three weekend letters that received the hand-cancellations, and whatever this was it doesn’t seem as straightforward as just proposing without further clarification that, well, that’s just how things were done at the weekend, and that’s that, because we have examples of weekend machine-cancellations also. Much, then, points towards the strong possibility that it was Zodiac himself who did something different with the three specific weekend mailings.

So, get the ‘right’ answers to the questions that remain and we could nail this. Get the ‘wrong’ answers, and we’re in that chasm of yours whether we like it or not!

Chaucer wrote:I agree re: certainty. This is a good line of inquiry, and i encourage it, but until we have eliminated other possibilities, I think we need to be cautious. I was quite excited and confident about the district codes and maps and obviously that was squashed. A healthy dose of skepticism is also required here, I think.

We need simple procedural facts clarified in order to move forward.

But I think a lot has been accomplished. I'm wondering if Law Enforcement was aware of what the codes actually meant.

And, until proven otherwise, the fact that Mare Island may be in the mix as a 'San Francisco' mailing location is significant.

Xcaliber wrote:I'm wondering if Law Enforcement was aware of what the codes actually meant.

The fact that, in at least one case, it can be shown that LE misinterpreted (misread) one of the postmarks as showing - what was it, “JB” instead of “1B” - when sending analysis requests to the FBI, this suggests to me that there is the real chance that they didn’t. Not as to the detail, at least.

Xcaliber wrote:And, until proven otherwise, the fact that Mare Island may be in the mix as a 'San Francisco' mailing location is significant.

It just so happens that today I posted the idea about one possible source of origin being Mare Island in a thread on Reddit. One Redditor, whose opinions generally I have a lot of time for, seemed inclined to want to immediate shoot the idea down as preposterous. His responses were quite quickfire - I think he said he was serving himself and on base at the time he was posting - and did have to back-track a little on his initial (essentially) “What the hell are you on about?” His doubt may yet be well-founded, ultimately, but it did get to the point where he was able to give one (?current) example whereby a 966 postcode was assigned to a vessel - 96674, USS Okane.

One of the other arguments put forward was that Mare Island “would have said ‘Mare Island’ or ‘Vallejo’ ... because Mare Island was an independent post.” However, it might be relevant here that, from information I had discovered some while ago, it appears that through the period 11 May 1965 to 31 Jan 1970, MINS and the San Francisco Naval Shipyard at Hunters Point were merged into a single operation, what was known as the San Francisco Bay Shipyard.