Cannon Ball Primer By Rusty Edwards

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Cannon Ball Primer By Rusty Edwards People frequently ask me if an iron ball they found or bought is a cannon ball?

This paper describes the process that I use to answer these questions. PBS has a program entitled History Detectives.

To investigate a possible cannon ball, you ll have to serve as your own History Detective. Here s the general process that I follow when I come across such an item.

1 Cannon Ball Primer By Rusty Edwards People frequently ask me if an iron ball they found or bought is a cannon ball? If it is, they want to know how old it is, what type of cannon fired it, and which conflict it was fired, i.e., the Revolutionary War, Civil War, etc. This paper describes the process that I use to answer these questions. PBS has a program entitled History Detectives. During the show, historians, researchers, archivists, and subject-matter experts investigate an historical item to discover its likely purpose and past use. To investigate a possible cannon ball, you ll have to serve as your own History Detective. Here s the general process that I follow when I come across such an item. First, I look at the object to determine if it is really a cannon ball. Many of these objects turn out to be industrial grinding balls, sports shot puts, or even decorative balls from an old iron fence or gate. Cannon balls are typically made of cast iron. I say typically because some very early cannon balls were made of stone or even lead. An old cast iron cannon ball, especially one that has been buried for many years, should have a dark chocolate colored patina and pitting. The extent of the coating and pitting will be closely tied to the type of soil, amount of moisture in the ground, and how many years the object has been buried. If I see a ball that lacks this dark chocolate appearance, Decorative ball from an old cast iron fence. and looks more metallic, I ll probably find that it s an industrial grinding ball. As the name implies, grinding balls are used by mills to crush, grind, and mix industrial materials like cement. These balls come in different sizes based upon the material being ground. When they are no longer needed, the balls are disposed of in various ways. Periodically, they make their way to ebay where they are sold to unsophisticated buyers as cannon balls. Metal grinding balls are made of forged steel, not cast iron. Steel is more resistant to rust, so they have a different appearance. Steel Grinding Ball Note: shinny appearance. Cast Iron Cannon Ball Note: Dark patina & pitting. 1

My next step is to confirm that the ball is not a sports shot put. A shot put and a cannon ball look similar. There are three things that I look at.

If the ball was found at or near a school or athletic facility it is probably a shot put.

Shot puts are used in athletic competition, so they adhere to a specific weight. After weighing the ball, I compare the ball s weight to known shot put weights (available on the Internet).

2 My next step is to confirm that the ball is not a sports shot put. A shot put and a cannon ball look similar. There are three things that I look at. Where was the ball found (if known), how much does the ball weigh, and are there any external markings on the ball? If the ball was found at or near a school or athletic facility it is probably a shot put. On the other hand, if it was located along a river bank, in the woods, or near a known battlefield, it is more likely to be a cannon ball. Shot puts are used in athletic competition, so they adhere to a specific weight. After weighing the ball, I compare the ball s weight to known shot put weights (available on the Internet). Next, I check the ball for marks. While not all shot puts are marked, many are. For example, an iron ball with a 16 enclosed in a circle is probably a 16 pound shot put. I m not familiar with anyone applying a similar mark to an actual cannon ball. Next, I inspect the ball for other markings. Most authentic Revolutionary War and Civil War cannonballs will not have numbers or letters stamped or molded on them. That said, a few Civil War cannon balls may have an arsenal Inspector s mark, which is typically a single letter of the alphabet. This is extremely rare, however. An iron ball with multiple letters probably isn t a cannon ball. The British Ordinance Department put a Broad Arrow mark on some of their 18 th and early 19 th Century cannon balls. This mark signifies the ball was the property of the British Crown. Not all British cannon balls have this distinctive mark. In every instance that I ve seen, it is handfiled into the ball s surface. During metal-casting, there typically will be a tiny amount of "seepage" by the molten metal into the mold's seam (where the two halves of the mold come together). When that happens, it was necessary for a foundry worker to remove the casting-seepage iron from the ball's seam-line after it cools and comes out of the mold. During the Civil War (and earlier), this work was ALWAYS done with a chisel, never with a file or a grinding-wheel. If you see file or grinding marks along the seam, the ball is unlikely a cannon ball. 2

Cast iron cannon balls were made as round as technology for the time would permit. An out-of-round ball would be inaccurate, and might get caught in the cannon s barrel, causing the barrel to explode.

3 I ve received a few inquiries from people who say they have an oblong or egg-shaped cannon ball. They may believe that it was either made that way, or deformed after hitting a large rock or other object. If you have such a ball, it s probably not a cannon ball. Cast iron cannon balls were made as round as technology for the time would permit. An out-of-round ball would be inaccurate, and might get caught in the cannon s barrel, causing the barrel to explode. Ordinance inspectors would check virtually every cannon ball to ensure they were the correct size, weight, and shape. For the latter, they used a tool (left) with a round opening the same size as the bore of the cannon from which the ball was to be fired. They would reject the cannon ball if it was misshapen. Yes, the shape of a cannon ball might change if it struck an immovable object, like a granite cliff. The part making contact with the rock would certainly show damage and may appear somewhat flattened. It is highly unlikely; however, that this kind of impact would cause a cannon ball to become oblong or egg-shaped. As stated earlier, it s very important to determine the exact weight and diameter of the ball. Of these tasks, getting the exact weight is probably the most difficult. Many people use their bathroom scale to accomplish this task. Unfortunately, most bathroom scales aren t capable of weighing small objects. I use a Post Office approved shipping scale for this purpose. It is far more precise. One person posted on a blog that he took his inert cannon ball to a supermarket in a paper bag and weighed it on a scale in the produce section. Another person said he put his cannon ball in a small cardboard box and had it weighed at his local Post Office. Most reference charts use a cannon ball s diameter (the distance across the widest part of the ball), not the cannon ball s diameter (the distance around the widest part of the ball). Few people have calipers large enough to measure the diameter of a cannon ball. Some folks hold a ruler next to the ball and attempt to estimate the diameter, but this seldom provides an accurate measurement. Here is a much better way to determine the diameter (width) of a cannon ball. 1. Put a piece of paper so one side rests against a vertical wall. 2. Put your ball on top of the paper with one side of the ball touching the wall. 3. Put a hard cover book against the opposite side of the ball. Be sure to keep the book vertical & parallel to the wall. 4. With the book against the ball, mark where the cover meets the paper. 5. Measure the distance from the mark to the edge of the paper that rested against the wall. Armed with the actual weight and diameter of the ball, I m now ready to look for information about the type of cannon that may have fired it. There are several web sites that provide useful 3

4 information about cannon balls. One web site is civilwarartillery.com. It provides several charts that are very useful. Here is one of them, which shows data about smoothbore cannon balls used during the Civil War. By knowing the weight and diameter of the ball, I m now able to determine the caliber designation of the cannon that fired it. For example, if my cannon ball is 2.84 in diameter, and it weighs 4.07 pounds, it was fired by a 4-pound smooth bore cannon. Some cannon balls, like the 4 pounder, were used during the Revolutionary War and Civil War. According to the TheCannonballGuy on treasurenet.com, Revolutionary War era cannon balls were a few hundredths of an inch smaller in diameter than Civil War era ones. Therefore, he says 4

Revolutionary War cannon balls will weigh a bit less than the Civil War ones listed in the chart above. Now that I know the caliber designation of the cannon that fired my cannon ball, i.e., 4- pounder, it s time to look up the maximum range for this particular cannon.

5 Revolutionary War cannon balls will weigh a bit less than the Civil War ones listed in the chart above. Now that I know the caliber designation of the cannon that fired my cannon ball, i.e., 4- pounder, it s time to look up the maximum range for this particular cannon. Fortunately, the same web site provides this information. In this case, I ll see that the maximum range for a 4-pound smoothbore cannon was approximately ½ mile. It s now time to connect the dots. Let s say I found a 4-pound cannon ball at a particular location. Using a map, I sketch a range ring extending ½ mile around the site. This means that the cannon that fired this particular cannon ball could be no further than ½ mile away, in any direction. As I study the area within the ring, I look for historical sites and/or events that involved military activity. I look for evidence of military engagements, old forts and military installations, etc. If the ball was found near water, I try to determine if there were any naval engagements or shore batteries within range of where the cannon ball was discovered. Here is a brief case study involving a cannon ball in my collection. It demonstrates how knowing: 1) the size and weight of a cannon ball, 2) the caliber of the cannon that fired it, 3) the maximum range of the artillery piece, 4) the location where the ball was found, and 5) the history of the area, can help you identify when and under what circumstances the ball may have been fired. In 1970, construction workers discovered a cannon ball buried in an old section of San Antonio, TX. Its diameter and weight revealed it was fired by an 18-pounder. Subsequent research showed that only one 18-pounder had ever been physically located in San Antonio, TX. This was the 18- pounder at the Alamo. Records show that this cannon fired several times during the famous siege. Most notably, the Alamo's commander, Col Travis, ordered it to be fired at Mexican forces in San Antonio immediately after they demanded the Alamo's surrender. An examination of the range chart confirmed that a ball from the Alamo s 18-pounder could reach this section of the city. Because of this circumstantial evidence, it is likely that the ball was fired by the defenders of the Alamo in So far, I ve focused on solid shot cannon balls. As the name implies, this type of ordnance is made of solid iron. These cannon balls do not explode; they use their mass and kinetic energy to destroy the target. They were used to smash a hole through the side of a wooden ship, punch an opening in the side of a building, or bowl through a formation of soldiers. Solid shot was a simple, yet fairly effective projectile against this type of target. It was the predominate projectile fired from muzzle-loading cannons until 1850, a full decade before the Civil War. Ordnance officers realized that an exploding cannon ball would be far more effective against troops in the open or behind entrenchments. To obtain this outcome, they created explosive 5

shells (as they were called) filled with gunpowder and equipped with a fuse. At first, these shells were designed to explode after hitting the target, or hopefully close to it.

These objects look very similar to a solid shot cannon ball, but will have a fuse (left), or perhaps an empty fuse opening (right).

6 shells (as they were called) filled with gunpowder and equipped with a fuse. At first, these shells were designed to explode after hitting the target, or hopefully close to it. As artillery fuses improved, some shells were set to burst over the target, showering the area with deadly metal fragments called shrapnel. People periodically buy or find an old shell. These objects look very similar to a solid shot cannon ball, but will have a fuse (left), or perhaps an empty fuse opening (right). Shells have an interior cavity for the explosive charge, so they weigh considerably less than solid shot. The previous chart shows that a shell for a 12 pounder weighs almost 4 pounds less than its solid shot counterpart. This significant weight difference is a key clue when attempting to determine if your cannon ball is a solid shot cannon ball or an identically-sized shell. Shells filled with old gunpowder can still be extremely dangerous! A few years ago I read about a deadly accident after a man attempted to weld several unexploded shells together into a pyramid-shaped pile next to a cannon at a Civil War memorial. The heat from his torch caused at least one of the shells to explode, instantly killing him. This tragic story demonstrates how old gunpowder in a 152-year shell can be extremely dangerous if improperly handled. If you re not sure, you should immediately contact your local police department for assistance. By using the History Detective methodology described above it is possible to confirm that an iron ball is indeed an authentic cannon ball and discover when and under what circumstances it may have been fired. I hope you find this information useful. 6

Late Period Cannon

Late Period Cannon 12-14-09 Early Bombards During the 15th century, artillery crossed a threshold in gunpowder technology from the big bombards. Bombards were developed to beat at castle walls, and the