as a royal order in 1765. (Its focus at the time was artillery more than muskets or handguns.) One of the accomplishments of the system was that solid cast cannons were bored to precise tolerances, which allowed the walls to be thinner than cannons poured with hollow cores. However, because cores were often off center, the wall thickness determined the size of the bore. Standardized boring allowed cannons to be shorter without sacrificing accuracy and range because of the tighter fit of the shells. It also allowed standardization of the shells. Before the 18th century, devices such as guns were made one at a time by gunsmiths in a unique manner. If one single component of a firearm needed a replacement, the entire firearm either had to be sent to an expert gunsmith for custom repairs, or discarded and replaced by another firearm. During the 18th and early 19th centuries, the idea of replacing these methods with a system of interchangeable manufacture was gradually developed. The development took decades and involved many people. Gribeauval provided patronage to Honoré Blanc, who attempted to implement the Système Gribeauval at the musket level. By around 1778, Honoré Blanc began producing some of the first firearms with interchangeable flint locks, although they were carefully made by craftsmen. Blanc demonstrated in front of a committee of scientists that his muskets could be fitted with flint locks picked at random from a pile of parts. Muskets with interchangeable locks caught the attention of Thomas Jefferson through the efforts of Honoré Blanc when Jefferson was Ambassador to France in 1785. Jefferson tried to persuade Blanc to move to America, but was not successful, so he wrote to the American Secretary of War with the idea, and when he returned to the USA he worked to fund its development. President George Washington approved of the idea, and by 1798 a contract was issued to Eli Whitney for 12,000 muskets built under the new system. Louis de Tousard, who fled the French Revolution, joined the U.S. Corp of Artillerists in 1795 and wrote an influential artillerist's manual that stressed the importance of standardization. Implementation Numerous inventors began to try to implement the principle Blanc had described. The development of the machine tools and manufacturing practices required would be a great expense to the U.S. Ordnance Department, and for some years while trying to achieve interchangeability, the firearms produced cost