From Boston Ways: High, By and Folk by George F. Weston, Jr., copyright 1957 Beacon Press and purchased for $7.00 at McIntyre & Moore:
Eels on Christmas Eve are as much an Italian tradition as is turkey on Thanksgiving for the New Englander. A few days before Christmas, metal-lined pushcarts appear on the streets. These are full of sea water--and eels. A crowd gathers around one of the carts to help an old, wrinkled Italian woman select her banquet. With the approval of the bystanders she indicates a noble specimen, full five feet from stem to stern. The vendor grasps him expertly and places him on the scales. Immediately he slithers off and back into the tank before his weight can be established. A huge paper bag appears from under the cart and the eel is dropped in, tail first; but before the mouth of the bag can be tied, the eel splashes back into his native element.
Excitement grows! The crowd takes sides! Some shout advice to the old lady, some to the vendor, and a considerable number call upon the saints to aid the eel.
Now the operator changes his technique and drops the eel into the bag head first. An exploring tail oozes out. The vendor seizes it, giving it a vicious bite. The tail withdraws into the safety of the paper sack. Quickly the neck of the container is securely tied and the bundle triumphantly placed on the scales. By this time the paper is so water soaked that the lithe captive has no difficulty in pushing his way right through the wall of his prison and back to freedom. The salesman admits defeat, loops a strong cord around the eel, guesses at the weight, and hands the other end of the rope to the elderly purchaser, who departs with a long black tail wagging in the dust behind her.
Peace again descends on Salem Street.
This book also contains a considerable amount of pictures of Boston "then and now" -- "now", however, being 1957. Many of the sights seen "now" are long-gone today. It's an interesting read to say the least.