This is CBS Island World. I'm John Batchel with Patrick O'Donnell, the author of the new book The Indispensibles, the story of the marbleheaders, the fishermen who become the strength of Washington's ability to cross water in the turmoil of the Continental Army battle with the British regulars,

first-rate British soldiers. It is now December 25th, 1776 at McConkey's Ferry on the Delaware River.

Washington's 2400 volunteers in winter quarters are ordered to cross the

river to attack Trenton, but crossing the river means that you must deal with ice flows in the

Delaware and another Nor'easter. Patrick, there's a photo, there's a painting at the Museum of Art in New York of Washington's Crossing.

It is not necessarily accurate because it was painted over 70, 80 years later, but it does convey the challenge of the river.

How did they do it, Patrick?

Is there an explanation for how they cross that river with those Durham boats?

They had Durhams and flat-bottom boats, John.

And yeah, it's the skill of the marble headers that once again bring the Army to safety.

All other attempts to cross the river that night failed, none of them got across it was only the marble headers and their skill in the boats that they were able to bring the

army across and this was a mission impossible the river was not cooperating the currents everything was

going wrong once again.

But it's the skill of the marble headers that they had developed in the Grand Banks.

It is also working as a team.

You know, many of these men were on fishing boats together.

And, you know, it's really quite unique.

Many of them were also, it's a diverse group.

You know, you have African Americans, three African Americans.

There's some Hispanic members in the unit.

All of these men work as a team.

It's a unit.

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