San Francisco to Vallejo does (and did) require the same postage as San Francisco to San Francisco.

Postage in the US is based on weight of envelope/package. A zip code is more like a routing number to a specific sectional center that delivers the mail to a particular region. The following is from Wikipedia:

ZIP codes are numbered with the first number representing a certain group of U.S. states. The second and third numbers represent a region in that group of states or, in some cases, a large city. The fourth and fifth numbers representing a group of delivery addresses within that region. The main town in a region (if applicable) often gets the first ZIP codes for that region. Other towns are often given ZIP codes in numerical order alphabetically.

Additionally, mail from the San Francisco/Vallejo region runs through the Richmond sectional center.

At Tom’s site a poster by the name of Sean had a question regarding the -pm on an envelope mailed by the Zodiac. I answered his question and provided detailed info on how the postal system in the US routes mail. I didn’t include the above info in as many words. If you are interested you may wish to look the post up.

Soze

Soze, on the issue of postmarks – how was it determined the Stine letter was mailed from the inner Richmond?

I havent, prior to my post above, done any digging into your question and so I may be wrong in what I’m about to say. I would say the giveaway is the 1A in the postal cancellation. The one appears to be a postal district. That district one covers what appears to be 7 adjoining neighborhoods within san francisco. The A represents the specific neighborhood. I’m not sure where you get "inner Richmond". The 1A indicates central Richmond. 1B would indicate inner richmond.

I would like to say nice find to whomever came up with that originally.

Soze

Curious….

Central Richmond- isn’t that the area where a call was made for a cab and Stine failed to make it? Or am I jumbling things up?

Soze

I believe Richard mentioned that the Stine letter was thought to originate from the Inner Richmond district.

(If the original Stine destination was 9th Avenue and Anza Street, that would be considered the Inner Richmond.)

The Inner Richmond begins at Arguello and California Street and goes west to about 13th Avenue (so 13 blocks, as Arguello is considered 1st Avenue).

So it would be possible to mail a letter at a mailbox in the Inner Richmond which was walking distance from the Stine crime site.

There is a post office on 10th Avenue and Clement Street. My guess, especially back then, is anything mailed at a standing mailbox in the neighborhood would end up at that 10th Ave post office, and it would be postmarked there.

I was also wondering if conceivably the letter was mailed Saturday night after the crime. If it were mailed in a mailbox Saturday night it likely wouldn’t be picked up and postmarked until Monday.

Thanks, I found it odd Zodiac placed 4 X 6c stamps on the July 31st Vallejo letter, but only 12c on the San Francisco letters.

I’m assuming the standard rate (1 ounce or less) back then was 6 cents.

It wouldn’t have been unusual to add postage if the sender thought they were over the limit.

(But it wouldn’t have had anything to do with distance.)

You might run the risk of needing a 2nd stamp if say, you were mailing 6 or more pages but 2 pages, no. That would only require a single stamp and I think, even then, people knew that. 4 is absolutely ridiculous. He had other reasons beyond mailing.

Given that the 1A designation seems to point to Central Richmond and not Inner I am still at a loss for why inner is being pushed.

Soze

Yes, the July 31st 1969 ‘408’ letters were franked in the Central Richmond District

It is an interesting discovery – essentially the same letters, but he doubles the postage on the Vallejo one.

Richard, can you confirm that the Stine letter was also postmarked in the Central Richmond neighborhood of SF?

I believe the Stine letter was Inner Richmond.
Dripping Pen Card-Twin Peaks West district, Balboa Terrace neighborhood

Another thought is someone may have assumed a letter from San Francisco to Vallejo would get there faster if it had more postage on it.

In 1969 there was still an ‘Air Mail’ option in the US, where for additional postage you were assured the letter would travel by air rather than by ground.

Obviously that didn’t apply SF-Vallejo, but that may have been the perception, that more postage equates to the fastest delivery time.

That is a good thought. Believing Zodiac was a resident of Vallejo, I was contemplating the significance of the wildly excessive postage.