[gregfjohnson]

I've been trying to find discussion of this topic on Hacker News between October 1582 and September 1752, but to no avail.

'cal 9 1752' is .. funny. I guess instead of doing this annoying a-periodic leap second business, they accumulated a bunch of leap seconds owed, and skipped 11 days at one go. Sysadmins at the time were of divided opinion on the matter.