Although versions of our modern baseball have been around since the beginning of the 19th century, the smallish, hard version we know today was first used in 1845. Despite the fact that some people claim baseballs have changed in recent years due to increased periods of home runs, Major League Baseball officials claim the baseballs have not been altered in any way in recent decades.
When baseball was first played, there was no uniformity in the way baseballs were made. Baseballs were either homemade or custom ordered from businesses that had the ability to make them. In 1872, in an effort to standardize the ball and therefore the game of baseball, weight and size requirements were established in the production of baseballs.
The original baseballs contained a round rubber core that was replaced in 1910 by a cork that allowed a lighter ball to travel through the air better. This was replaced 20 years later by a cushioned cork that could take a hit better than the other cork. Since then baseballs have undergone only one major change that happened in 1974 when the outside material changed from horsehide to cowhide.
When used in a Major League game, the average baseball must weigh between 5 and 5.25 ounces and measure between 9 and 9.25 inches in circumference. The average amount of play a standard Major League baseball gets is five to seven pitches before a new ball is chosen. This makes for roughly 600,000 baseballs used throughout all the Major League teams per season.
An official Major League baseball is made, quite simply, starting with a round cushioned cork center (called a pill) and wrapped tightly with yarn made of wool, polyester and cotton, then covered uniformly in hand-stitched cowhide.
The core of the modern baseball is a round piece of cushioned cork (a cork and rubber composition) that measures just under an inch in diameter. This is then surrounded by two layers of rubber that increase the circumference to 4.125 inches.
This core is then wrapped in four layers of yarn made of different components of wool, polyester and cotton. This material can be up to a mile long, wrapped very tightly around the rubber part of the core. Wool was chosen as one of the materials because it is a resilient material that allows it to be able to have pressure repeatedly applied to it (such as being hit with a bat), and yet retain its original shape and integrity. A blend of cotton and polyester was chosen as the outer material used because it adds strength and reduces the risk of tears when the outer cowhide cover is applied.
The cowhide cover comes primarily from Midwest Holstein cattle because these hides have a better grain and are smoother and cleaner than most cattle in the United States. These covers are pre-punched with holes where the stitching will be done. The 88 inches of red cotton thread are hand-stitched with a custom-made needle. This stitching process was tried out with machines, but it was found that hand-stitching created a more uniform and reliable product.