That's not all, Dan. I'm buying some very fine palm chisels from Pheil in Switzerland to make a lino or woodblock carving to print a few Christmas cards in a limited edition. I too was sorting tools, checking whether any of my oil- and Japanese water-stones are the right grit and size (all too bloody big -- and a properly shaped Arkansas slipstone is expensive this side of the water). Lying in a toolbox I looked into was a huge spanner (wrench to Americans) stamped on each side in two gauges, Whitworth and BSC. Hey, hey, hey, didn't someone mention British Standard Cycle the other day? I appears that they're compatible, except that x measure in Whitworth is equivalent to y measure in BSC. And I already reported that, looking through my large spanners with the metric-head Rohloff sprocket socket in hand, I found that a Whitworth spanner was a tight fit.
The threads may be different for a reason (at a time when it was understood that a reason to be good was rational, not your feelings), but the nuts' across-the-flats distance is the same for economy in buying tools. Looks like those old guys weren't so wayward after all.
