On Display Today

Today from 1 to 5 the Easton Historical Society will be displaying something you've never seen before: pieces of one or perhaps two Revolutionary War cannons. Chaffin's History of Easton tells us that Captain James Perry made cannons and cannonballs during the Revolutionary War. Legend holds that George Washington came to Easton to visit Perry's blast furnace during the siege of Boston. The size of his furnace probably precluded casting cannon big enough to fire from the American lines into Boston. But what size cannon could Perry make?

Down range from the Old Pond Dam is an embankment that was used to catch the cannonballs fired during the proofing of the cannons. Several of these cannonballs have found their way into the Historical Society's collection, but not all have been connected to the embankment which is the only guarantee that a cannon big enough to fire the cannonball actually existed. Perry simply could have made large shot for ship cannons that already existed so the question of the size of his cannon remained.

Casting a cannon in one piece with the bore included was fraught with problems. First, as with all castings there could be imperfections caused by an improper pour. Second, the molding that created the bore might be slightly crooked or not of uniform size. These problems were so severe that by the time of the Revolution some cannons in Europe were cast in one solid piece and then drilled out. This was actually tried in a furnace in Sharon, but it was too difficult a technical feat to succeed given colonial machinery. Here in Easton, the way these problems were overcome was to overload the new cannon with extra powder and shot and fire away. If the cannon didn't explode or send a cannonball off in some wild direction, it was saleable. Otherwise, in theory at least, it could be melted down for another try.

The great local historian Kippy Grant once told Duncan Oliver about pieces of a cannon that were fished out of Old Pond during the Depression and sold for scrap. Frank Meninno tells a story about someone finding a piece of a cannon many years ago. Recently, however, two different groups of people have discovered pieces of what are certainly one or more cannons. The pieces are large fragments and suggest that they exploded on proofing. They seem to come from about the same spot which may have been a dump for Perry's furnace although why the chunks weren't remelted remains a mystery.

Several people have used everything from Captain Elisha Harvey's military calipers to geometrical calculations, to setting cannonballs, coffee cups, and soda bottles in the bores to determine the caliber of the gun. This is a complicated process. First, the fragments only give us a chord of the bore not a radius thus creating a difficult problem in geometry. Second, English cannons were standardized by the size cannonballs they fired with 3 and 6 pounders being common for field artillery, for example. However, they also wanted to standardize the bore in good old English inches or reasonable fractions, but a three pound ball doesn't work out to an easy 3 inch or 3.5 inch bore.

Then there is windage, the amount of space you leave between the cannon's interior wall and the cannonball. By British standard this was supposed to be a proportion of 21/20, a pretty tight fit. When a round shot is fired in a smooth bore, the ball actually bounces up and down in the barrel as it is fired. A good relatively tight fit makes the bouncing small and gives the gun accuracy. Too much windage and wear on the barrel increases and the shot is liable to fly out of the barrel with no consistency. After studying this situation for a week, we feel that colonial cannon makers probably allowed more windage then their British counterparts to make up for inferior bore casting.

What does all that huffing and puffing mean? We're pretty sure that one piece is from a 4 pounder. This was a piece of artillery that could be fitted on a galloper carriage for use with the infantry in the field. It was probably a piece this size that Captain Harvey pushed over a cliff to prevent their capture by the British during fighting around New York. The chord of the bore on a second piece is harder to measure, but it seems to have come from a smaller cannon perhaps a 2 pounder although this is by no means certain.

Mysteries remain. Yesterday, we took two cannonballs to the Easton Farmer's Market to be weighed by Val Souza who has the traditional hanging scales. One ball weighed in at about 3 and a quarter pounds and the other at about 4 and three quarters pounds. Neither were standard sizes much may be caused by a variety of things from rust to the problem mentioned above-you can have standard weights or standard calibers, but you can't have both! The overweight 4 pounder was found in the embankment area so it likely fitted one of Perry's cannons. We have one larger ball that we didn't weigh yesterday for fear of breaking the scale, but one thing all this math has taught us is that the weight of the cannonball increases much faster than the diameter of the ball. The caliber (the diameter) was used to determine the other proportions of the cannon so our 4 pounder was between 15 and 25 calibers long-4 to 6.5 feet. A 9 pounder, our best guess at the weight of the biggest ball, would only have a caliber 1 inch bigger than the 4 pounder meaning the barrel length would fall in the 5 feet to 8.75 feet range. Since the daily pour of the blast furnace had to be at least enough iron to cast one whole cannon (they weren't cast in pieces), these calculations show that if the furnace produced enough iron to cast a 4 pounder, it could probably produce enough to make a 9 pounder.

All this speculation from some rusty pieces! It makes me long for standardized parts, but the point is we are showing off parts of a cannon forged during the War for American Independence in Furnace Village, not North Easton, by somebody named Perry, not Ames. Come see it!