Boy that took some finding in the HP archives
http://www.hpl.hp.com/hpjournal/pdfs/IssuePDFs/1965-04.pdfHank Taylor shares some interesting background on it on page 21 of his memoirs
http://www.kennethkuhn.com/hpmuseum/hpmemory/an/pdf/Taylor_Memoir_120503.pdfLOL try this today and make sure you name isn't Mohamad
The clocks usually traveled !/2-fare as "children" (230 Ibs. each) and occasionally as excess baggage or cabin freight.
It appears to that it was checking the relativity adjustments made to certified time clocks in each country. So what they did was take these two clocks around to make sure each countries National Standard agreed with each other.
So it would probably be classified as an indirect test of relativity but historically I found the whole thing fascinating. Things are so much easier these days you forget how hard this stuff would have been to do. The efforts just to set the national standards was just the beginning of that process that embedded relativity in the middle of science and development.
Compare that to the sort of modern atomic clock on a chip which comes in at 35 grams and around $1500.
http://www.microsemi.com/products/timing...le-atomic-clockThe irony for those that don't accept relativity is that it is embedded in most of there new gadgets that they use