The purpose of two structures floating in Portland and San Francisco harbors remains a mystery, but the anonymous owner has left clues to the projects’ high-tech ambitions: inside jokes that computer geeks might find hilarious.

The strange-looking buildings floating on barges are made of shipping containers, welded together. Some experts have speculated that they will be floating data centers. The search engine giant Google received a patent five years ago for a proposed floating data center that uses the ocean to provide cooling.

In Portland, the barge is docked at Rickers Wharf, where Cianbro Corp. is installing undisclosed technological equipment inside the structure.

Even workers on the project aren’t being told about the structure’s purpose or the owner’s identity.

In San Francisco, the barge is docked at Treasure Island, a former Navy base.

According to vessel registration records, the barges in Portland and San Francisco are owned by a Delaware company called By and Large LLC. The company owns four barges, BAL0001, BAL0010, BAL0011 and BAL0100.

In the binary code system used by computer programmers, the last four digits of each of the four registration numbers spell out “one,” two,” “three” and “four.” The barge in Portland is BAL0011, apparently code for “barge number three.”

“That’s a little telling,” said Sharon Gaudin, a writer for Computerworld who went to Rickers Wharf on Monday to eyeball the structure but was ordered off by Cianbro workers.

“The tech world is abuzz about it right now,” she said. “I’m trying to figure out why Portland, of all the places they could go.”

Two barges, BAL0001 and BAL0010, are in San Francisco. BAL0100 is unaccounted for.

Here’s another bit of geek humor: the name By and Large may be a reference to “Buy N Large,” the fictional mega-corporation that has taken over the world economy in Pixar’s 2008 film “WALL-E.”

Gizmodo, a design and technology blog, speculated Friday that Google is creating a robot as part of its plan to create an island nation.

“Though I’m sure if Google is building WALL-E, Apple’s EVE shouldn’t be too far behind,” Gizmodo said.

From Portland Harbor, it appears that the structure consists of 63 metal shipping containers welded together.

The structure is four containers high, four containers wide and four containers long. One container is slanted at a 45-degree angle to create a ramp.

There are doors on each of the upper three floors on both ends of the structure. There are also narrow windows.

It’s possible to look through some of the windows and see windows on the other side, indicating that the sides of some of the containers have been removed to create open floor space.

Google has refused to return all emails and phone calls from reporters who have inquired about the project.

Citing anonymous sources inside Google, a San Francisco television station, KPIX, is claiming that the structure there will be a floating store for the Google Glass, the cutting-edge wearable computer the company is developing.

The station says that Google hopes to tow the completed structure to San Francisco’s Fort Mason, where it would be anchored and open to the public.

That idea doesn’t make sense, said Cliff Goudey, a senior engineer at Maine Marine Composites in Portland. No company go through that much trouble to create a retail space, which can be had easily on dry land, he said.

Goudey said a floating data center makes more sense because it takes an enormous amount of energy to keep data centers cool.

The company would save a lot of money if it could cool its servers with sea water rather than air conditioners, he said. The ocean would be like a “heat sink,” he said.

Even so, the masterminds of a floating data center probably wouldn’t want to use the word “sink.”

Tom Bell can be contacted at 791-6369 or at:

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