At least they're not ten-ton Grand Slams...
Odd that they seem to have been found before, though..
We had a stick on the factory in WW2 and only one really went off, and nobody really knew how many there had been, either. Around 1985, we were digging a pit in the test area and hit an object about 15" diameter, where there was not supposed to be anything - it turned out to be an unknown, abandoned drain-pipe, but it was exciting for a while....