... A "period" alternative is to put the mail into a heavy canvas bag with some sand and some straw, and hand it to your squires to use as a "medicine ball" for some exercise for an hour or two...
Hey I've got a squire!
"Sinbad! Come over here! Dad has a new ball for you to play with!"
Cheers
-See it there, a white plume
Over the battle - A diamond in the ash
Of the ultimate combustion-My panache
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