hello friends, please enjoy. November 4 1846: The first US patent is awarded to Benjamin Palmer for an artificial leg. 1862: A patent is awarded to Richard Gatling for his rapid-firing Gatling gun, although Union forces would not use the weapon until the siege of Petersburg, Virginia, in 1864. 1939: Air-conditioning makes its first appearance in an automobile, a Packard prototype, exhibited in Chicago. much love and many blessings,kathy martin