It was a bittersweet moment on the summer day in 2014 in New Bedford when Mystic Seaport's whaling ship, Charles W. Morgan, made a return visit to its original homeport, once the whaling capital of the world.

It seemed then the Seaport's grand feat of bringing the last wooden sailing ship back to New Bedford Harbor could never be topped, in terms of a modern retelling of the great history of American whaling.

That may be true. It surely made whaling history enthusiasts of New Bedford a bit envious of the Seaport's prize artifact.

But the New Bedford Whaling Museum has a grand feat of its own up its sleeve, one that could give the Morgan's 38th Voyage of 2014 a run for its money, for those interested in whaling history.

The New Bedford museum has completed a $400,000 restoration of its Purrington-Russell "Grand Panorama of a Whaling Voyage 'Round the World" (a title befitting its size) and is exploring how to exhibit it.

The panorama, painted in 1848 by Benjamin Russell and Caleb Purrington, depicting an entire voyage around the world aboard a whaling ship, is considered, at a quarter mile in length, to be the longest painting in the world.

It was taken on national tour shortly after it was finished. It was held on giant spools, which were unwound before an audience, accompanied by music and narrative, to create a live entertainment with the painting.

A part of it was even displayed at the 1964 World's Fair in New York.

Over the years, the painting, which is on a thin fabric, became too delicate to be displayed. In 2010, the New Bedford Museum, then in the midst of expansion and renovations, put the panorama in storage in the textile archive space at Mystic Seaport.

About a year and a half ago, they reclaimed it, big spool by big spool, and began the conservation, which has been done in a public display in New Bedford.

"It really is extraordinary, the way it documents the whaling industry at that time," said Paul O'Pecko, vice president for research collections at Mystic Seaport, who enjoyed the opportunity to examine the panorama while it was here.

Indeed, there is a Mystic connection, since the Charles W. Morgan is included in the painting, captured on a visit at the time to the Azores.

Tina Malott, director of public relations for the New Bedford Museum, said plans still are being worked out how the restored panorama will debut and how it will be displayed after that.

The museum has been fielding a lot of interest from the around the world from places who would like it to stop on a tour. Consideration is being given to visiting some of the same American cities where it was displayed after it was first painted.

Mystic will be considered for both the debut display and any travel route the panorama makes, Malott said, and talks between the two museums have been planned.

A principal consideration is space, since it is estimated 16,000 square foot space would be needed to fully show it. There may a way, Malott said, to display it in some kind of snaking pattern.

It can't really be unspooled as it was for the original demonstrations because of the delicate condition of the fabric.

"It's a priceless object for us," she said.

There are plans to create a digital copy and it could be possible to spool and unspool the replicated version, Malott said.

"We are in the thick (of planning) right now," she said. "We will be whittling down the options."

Plans should be complete by February and the first exhibit could be before next summer.

"We will start rolling it out, literally," she said.

This is the opinion of David Collins.

d.collins@theday.com