were Jan Matzeliger, who developed the first machine to mass-produce shoes, and Elijah McCoy, who invented automatic lubrication devices for steam engines. Granville Woods had 35 patents to improve electric railway systems, including the first system to allow moving trains to communicate. Garrett A. Morgan developed the first automatic traffic signal and gas mask. Lewis Howard Latimer invented an improvement for the incandescent light bulb. More recent inventors include Frederick McKinley Jones, who invented the movable refrigeration unit for food transport in trucks and trains. Lloyd Quarterman worked with six other Black scientists on the creation of the atomic bomb (code named the Manhattan Project.) Quarterman also helped develop the first nuclear reactor, which was used in the atomically powered submarine called the Nautilus. A few other notable examples include the first successful open heart surgery, performed by Dr. Daniel Hale Williams, and the air conditioner, patented by Frederick McKinley Jones. Dr. Mark Dean holds three of the original nine patents on the computer on which all PCs are based. More current contributors include Otis Boykin, whose inventions included several novel methods for manufacturing electrical components that found use in applications such as guided missile systems and computers, and Colonel Frederick Gregory, who was not only the first Black astronaut pilot but the person who redesigned the cockpits for the last three space shuttles. Gregory was also on the team that pioneered the microwave instrumentation landing system. Terminology General The term African American, popularized by Jesse Jackson in the 1980s, carries important social implications. Earlier terms used to describe Americans of African ancestry referred more to skin color than to ancestry. Other terms (such as colored, person of color, or negro) were included in the wording of various laws and legal decisions which some thought were being used as tools of White supremacy and oppression. A 16-page pamphlet entitled "A Sermon on the Capture of Lord Cornwallis" is notable for the attribution of its authorship to "An African American". Published in 1782, the book's use of this phrase predates any other yet identified by more than 50 years. In the 1980s, the term African American was advanced on the model of, for example, German American or Irish American, to give descendants of American slaves, and other American Blacks who lived through the slavery era, a heritage and a cultural base. The term was popularized in Black communities around the country