my father was a Western Union lineman...he set poles and ran lines all thru the west, but he liked to tell of being in some little town in Wyoming where they had been working straight thru some pretty cold weather...but there was also an 'official' weather bureau thermometer there, which registered down to -50°...and one day they went out, and found that thermometer BROKEN...they did NOT work that day!..(I suppose that, after that, they had to make do with specially configured Brass Monkeys ;>))......