This is one of the nicer stations. Still looks like a 19th century dungeon, though; which of course, it is.


One of the nicest things about the subway stations is the porcelain-tile wall art. Since the trains are always late, one can spend a lot of time observing these oddities.

But have you noticed that it’s not trivial to make these pieces all line up and look nice — because the letter strokes make non-right angles? See how the tile alignments are fudged, near the bend of the letter Y on the left side? There is a long side of a triangular piece aligning with a side of a square piece, where the hypotenuse of the triangle has to be a little bit longer. So they just jam it in there. It sticks out a little bit.

And here is a letter V. Clearly when they do the tiles, they make each line of tiles for the \ strokes before the corresponding / strokes, because the \ tiles run longer.

These were all taken at the station called 23rd and Ely. Of course the station names don’t correspond to where the exits are. One stop at 49th Street actually produces exits mostly on the 47th Street. Another at 42nd Street actually opens onto 40th Street. Go figure. Actually, station names in Manhattan itself are almost consistently “wrong” in this way, which leads me to believe that Manhattan streets have been renumbered at some point.

The USPS is complaining that the Netflix mailer costs too much to process because it is, in practice, non-machinable, even though it qualifies for a machinable discount; and, its reply rate is too close to 100% for the discounted business reply mail to be profitable. Sounds to me like broken cost modeling by the USPS.

Netflix clearly spent some time designing their mailer. A disc by itself in the paper envelope is just a hair under 1 oz. And the Netflix envelope has that useless floppy flap because the aspect ratio of a machinable letter-class mailpiece has to be between 1.3 and 2.5. Even USPS says

Currently, the envelop design with the floppy leading edge meets these criteria, as none of the negative characteristics listed in the DMM specifically apply to this type of mailpiece.

But there is one thing I don’t understand. If a mailpiece is “too rigid,” then it ceases to qualify for the machinable rate. Look at the definition of “too rigid”:

Does not bend easily when subjected to a transport belt tension of 40 pounds around an 11-inch diameter turn

Okay, an 11-inch diameter is not that large, and putting 40 pounds of force on a DVD is sure to shatter it to pieces, so how is a Netflix mailpiece not “too rigid”? And if it isn’t too rigid for Netflix, then it shouldn’t be too rigid if I mail a disc, right?

So I tried exactly that. I put a disc in a 6″x9″ bubble mailer. It was maybe 1/8″ thick and weighed 1.5 oz. (if I put it in a jewel case, it would be in the range of 3-4 oz.)

It should cost $0.58 (first class letter rate for 2 oz.), right?

Even if, to be fair, it were considered “rigid” and hence non-machinable, it should still cost just $0.58 plus a $0.17 non-machinable surcharge. However, the postman insisted that I pay for the package/parcel rate of $1.30. I don’t understand why.

Actually, what he said was, this envelope is too small to be a “flat” (true) because a flat has to be 11″ (false) and it doesn’t contain a letter (that shouldn’t matter). I’m surprised a postman is so confused.

In Chinese, there is this elementary passage which plays on the homophone issue of spoken Mandarin Chinese. Every character in the entire passage is pronounced “shi” (with varying tones), but nevertheless at this level the passage would make no sense if recited. But, written in the Classical Chinese idiom, the passage makes perfect sense when read visually (and isn’t particularly difficult to comprehend even for a modern reader).

《施氏食狮史》
石室诗士施氏，嗜狮，誓食十狮。施氏时时适市视狮。十时，适十狮适市。是时，适施氏适市。氏视是十狮，恃矢势，使是十狮逝世。氏拾是十狮尸，适石室。石室湿，氏使侍拭石室。石室拭，氏始试食是十狮。食时，始识是十狮，实十石狮尸。试释是事。

This is one demonstration that written Chinese can hold significant semantic content beyond phonetic value, a mechanism that has been key for tying together diverging spoken dialects over a thousand years.

Part 5.

The tide turns (rather quickly)

After the exceedingly annoying but ultimately inconsequential ext2 interlude, I’m back on track with the original problem of recovering data from the broken Seagate drive.

After the disaster with file-copying using the Windows ext2ifs driver last time, I made sure to make a copy of the disk image while the external USB drive holding it was mounted under Knoppix Linux. The destination was another external drive formatted with ext2.

There is a lot more to do and this project is far from over, but I can see the end-game now, and so the recovery effort can be declared a success.

Lessons today:

• MIP is pretty useful, but I still won’t buy it.
• NTFS is truly robust, and the NTFS version of chkdsk is remarkable.

On to Part 6.

* Edit: I’ve since found a free tool called vdk that makes Mount Image Pro obsolete. Yes, it mounts ddrescue images. Yay!

Let’s see, it all started with somebody wondering if you can get a letter back from the postal service once it has been mailed, but before it has been delivered. Maybe you changed your mind about sending the letter, for example. I still don’t know the answer, but I’m guessing if there is no return address on it, forget it. If there is a return address, however, it ought to be possible, right? The sender will get the letter back normally in the case that it is undeliverable, so the sender is essentially a secondary recipient. What does the postal service do with undeliverable mail that has no return address anyway? Shred it? Anyway, this doens’t seem like a satisfactory conclusion in any case, that the return address should play an unrelated role in the mail interception problem.

Which brings me to the second topic. If we abstract away the implementation details and take the return address to be a bona fide secondary delivery address, then we can do some unexpected things, for example,

• What if put the destination address in the return address position and put a bad address in the destination address? The mail still gets delivered…
• But wait, undeliverable mail is only one of many conditions for returned mail. Insufficient postage is another. So don’t even bother putting a stamp on there…
• Now, sometimes, the postal service delivers the mail anyway, so for recoverability, swap the return and destination addresses; this way, you at least get the mail back if USPS is too nice.
• Even better, for automatic redundancy, put the destination address in both the return address and destination address positions, so no matter what, the postal service delivers the mail.

Wow, I like this already (“this” being the idea, not actually doing it). If Wikipedia is to be believed, the blatant scam in the last scheme is actually legal and works. But I’ve also heard the postal service sometimes delivers with insufficient postage but bills the recipient for postage due mail.

The few times I messed up with first-class postage raises, I’ve got mail back with insufficient postage. Which makes me wonder about the the price of first-class postage. In 1993, it was $0.29. Today (2006) it is $0.39. That’s pretty much in the inflationary range. With the proposed hike to $0.42 next year, there is also this new thing:

The post office is planning a ”forever” stamp for letters, good no matter how many times postal rates increase. That means people could say goodbye to those annoying 2- or 3-cent stamps that have to be added to letters every time rates go up. The idea for the special stamps, which would be sold at the same price as other first-class stamps, was included in proposals announced yesterday that would also raise stamp prices 3 cents — to 42 cents — next year.

That’s nice, you can buy floating-value stamps. The comments that follow in the link are even more interesting…(*) I’ve never seriously thought of postage stamps as a money instrument before. Of course you can buy them on ebay and sometimes stores for a discount (never understood where the discount comes from… value of liquidity?), but those are not as explicit as the derivative market that may result from the trading of “forever” stamps just before and after a rate hike. Can you imagine the run on “forever” stamps before a rate hike by arbitragers and eBay hawkers? Will there be a ration or what? Or as somebody in the comments suggested, they really shouldn’t be sold for X months prior to a rate hike (X depending on interest rates and percentage of hike). Let’s see how this pans out. I still send first-class mail, after all, even without the interest in derivatives.

Actually, when I first read about “forever” stamps, I was confused, because I’ve seen non-denominated stamps before that just say “First Class USA” and I had wondered whether they acted like “forever” stamps. I’ve just assumed they had whatever value they were purchased at. Of course this is correct – they are distributed right after a rate hike before stamps with the newly approved price is printed, and are worth the price at the time of purchase. But it must get confusing, if not for the postman then certainly for me… recently there has been a plethora of flag designs… I can’t remember which is which. Well, here are some that I recall seeing fairly often and recall wondering about their values:

$0.05	$0.10	$0.10	$0.25
$0.29	$0.32	$0.32	$0.33
$0.34	$0.37	$0.39	$0.41

More of them here. All right, that’s it.

(*) There is some mention in the comments about some arbitraging scheme of postages denominated in different currencies. This is a nice idea that actually has some applications in online forums, and will be discussed in another post.