This style of axe with a short, heavy poll and a short blade is a style that became quite popular amongst American consumers by the middle of the 18th century. Although likely one of a number of styles made in England it became so associated with this continent that it is often called an “American style” axe.
Axes, like most tools, are a mixture of iron and harder steel. Steel is an alloy of iron and carbon, making it harder and able to hold a sharp edge longer than iron. Steel was expensive to produce in the 18th century and it was only used where it was absolutely needed. Axes were made in two halves, half of the eye was hammered open on each side, then the two halves were welded together with heat and pressure. A steel bit was sandwiched between the two pieces of iron to form the cutting edge and was welded in place.
This is a felling axe. Types of axes varied dramatically in the 18th century and specific types were made for hewing timbers, cutting mortises, making wheels, barrels, and ships. This axe was primarily used to fell timber. The heavy poll made this axe well balanced. Many have been found in the ruins of Fort Ticonderoga suggesting how common they would have been, and used for a variety of construction projects.
American forces faced a dramatic shortage of tools as they fortified the Ticonderoga area in 1776. The commander, General Horatio Gates, requested supplies of tools from the surrounding states, and the Governor of Connecticut, Jonathan Trumbull, responded by forwarding nearly 1,000 axes from that state to Ticonderoga. This may be one of those axes. It appears to be an American-made copy of an English manufactured style that was popular in the colonies before the war.