The Arcadia “Dry Run”, (June 1929)

Prior to Michelson beginning construction of his Irvine Ranch evacuated tube late in 1929, he performed a test of the proposed Irvine Ranch apparatus on a railroad track in the town of Arcadia. There would be no tube in place for this work, merely the end mirrors contained in their housings, separated by 1,100 feet along the railroad track.

There is little documentation of this short-lived effort, however the Los Angeles Times did a story on the project in their June 6, 1929 edition, shown below:

Los Angeles Times, June 6, 1929

Also, contained within the engineering drawings on file in the Mount Wilson archives is a sheet showing the Arcadia setup, including concrete piers to be constructed to support the mirror housings. It clearly appears to be a direct forerunner of the Irvine Ranch installation.

Finally, there is actually some film footage showing bits of the Arcadia setup. One of the major facilities at the US Navy’s China Lake base are the Michelson Laboratories (Michelson attended the US Naval Academy and served in the Navy). At some point in time, I’d guess the 1960s, the Michelson Laboratories made an 8 minute film of Michelson’s scientific contributions. Like so many things, it eventually ended up on the Internet, which I’ve linked to below. The parts of the film between 4:57 and 6:37 show Michelson demonstrating how he would take measurements using the apparatus set up at Arcadia.


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