Because of recent model boat requests, I need to refocus my inland navigation research from the Mohawk-Oneida navigation of New York State in the 1790s to the Delaware River navigation of New Jersey and Pennsylvania in the 1770s; very specifically the events of December, 1776, where the Continental Army needed to arrange several crossings of the river by "borrowing" boats in use along the river by civilians.
No doubt everything that would float was pressed into service, and the variety of civilian vessels available was probably as broad as shown in the above 17th century view of a European river. Here we can see a number of boats, some poling boats, some rowing boats and at least one small sailing boat.
Although the majority of Delaware River boats would have been typical of those found on most American rivers, the one which was not, and which has been given the most historical attention, was the Durham boat, (below) which was an industrial "truck" used to haul stone, ore, pig iron, and various other cargoes for the Durham Iron Works up and down the river.
Yet as interesting as these boats might be, a great many other vessels were involved in the Crossing, the most significant being the several ferries used to haul the artillery across the river (below). In his book "Washington's Crossing" author David Hackett Fischer states "The ferries were best for the army's horses, artillery, and ammunition wagons. The Durham boats with their high sides and sharp ends were excellent for infantry."
I have a page about these early ferries at my ferries webpage.
Ferries were nothing more than an elaborated version of the basic "scow" or "flat (above), a universal boat type because it represents the cheapest and easiest way to create a transport for goods on water, excepting, of course, the raft, which was reserved mostly for timber.
These boats were nothing more than a shallow rectangular watertight box of wood, with the front and back edges sloping upward to lower water resistence and make passage easier.
Ferries like that above generally had gentler sloping ends than most cargo flats or scows, because the carriages, wagons, livestock and people needed to have an easy entrance and exist ramp, whereas cargio was usually loaded and unloaded over the sides of scows.
Fischer quotes one soldier involved in the Crossing...
This probably was not a ferry. Unless this soldier had never seen a river, it is unlikely he would not know a ferry when he saw one. It would be like one of us hearing someone saying "I rode to the city in a truck..." and wondering if he really meant "...a bus."
He cites another eyewitness account.....
So "scow"...."wood flat"... "ferry"....? Was there much of a difference? Apparently there was. Notice the finer points of boat terminology in the following legal extract from the laws of Kentucky in the 19th century:
So a "wood flat" was a specialized type, differentiated from a "ferry flat", and from a generic "flat boat" AKA "Orleans boat" (see below).
An early 19th century source further differentiates between types of "flats", suggesting a "wood flat" was a very specific type of scow or flat:
So here the flats were identified by what they were designed to carry; in this case dredged bottom mud, as shown above, versus timber. The text suggests this meant a design difference, not merely a functional difference. If any flat could serve any purpose, wouldn't the account just say "...three flats were completed..."?
But the finer points may not have been familiar to people in the Army who were not river-dwellers:
While this may appear a blending of the terms "scow" and "flat", it reads more like an explanation for the reader unfamiliar with the boats, being presented long after the event.
So for the time being we may assume there were many scows (a generic term) on the Delaware when Washington's troops arrived to collect boats for the several crossings.... employed in a variety of civilian pursuits, from the large ferries that operated at their normal crossing points down to the humble flats used to carry anything and everything, and everywhere.
Some hint of what the range of scows and flats on the river might have looked like is presented below, in a 19th century photograph of a scow building yard adjacent to a river. Note the variety of dimensions, all sharing a similar design.
At the very high end of the scow/flat continuum is the boat shown below. The same design....just on a MUCH larger scale!
...and it looks like a "wood-flat", too!