The fine Richard Thompson song named seems straightforward enough except for the first verse, which goes:

"See the boys out walking, the boys they look so fine,
dressed up in green velvet, their silver buckles shine,
Soon they'll be bleary-eyed under a keg of wine,
Down where the drunkards roll...".

Is this a specific historical reference? Did Richard have in mind 18th-century seamen? Does anybody know? Please advise. Thanks. Denis