LEWISVILLE- Jack P. Clark, 76, died unexpectedly on Tuesday June 14, 2011 in Ringgold, Georgia. A son of the late Harry M. and Gladis (Burk) Clark, Jack was born in Cambridge City, Indiana on August 1, 1934. Due to the early deaths of his parents, Jack was raised by his sister Marguerite Green Painter and her husband Harold Green and grew up in Lewisville. He graduated from Lewisville High School and was a member of the Lewisville Presbyterian Church. After high school he entered the University of Cincinnati where he earned a degree in Mechanical Engineering. Following the University of Cincinnati, he became part of the General Electric Space Program in Cincinnati, Ohio. During this time he was a participant in the Apollo Space Program and developed the battery that was used in the rocket that was sent to the moon. After leaviing the space program, Jack moved to San Jose, California where he became manager of the Research and Development Division of General Electric Nuclear Power Division. In his service there he received 13 patent awards from General Electric for patents he personally developed for the nuclear program. He was also recognized by the Nuclear Regulatory Commission for his development of a procedure that is still in use today which detects problems within a nuclear reactor. Survivors include his wife Charlotte of Ringgold, GA; 3 children, Jeff Clark of Watsonville, CA, Diane Clark-Smith of Lathrop, CA and Jerry Clark Mountain House, CA; 2 sisters, Esther Matthews of Cambridge City and Marguerite Painter of Lewisville; 2 step children, Ron Hayes and Jan Gibson of Ringgold, GA; 6 grandchildren; 3 great grandchildren; 2 locally living nieces, Linda Ross of Cambridge City and Marianne Noland of Milton. Jack was preceded in death by 2 brothers, Robert and Charles Clark and a special nephew, Richard Green. Funeral services will be at 11 a.m. on Wednesday June 22, 2011 at the Lewisville Presbyterian Church. Rev. Peter Zinn will officiate and be assisted by the Reverends Arthur Whitaker and Mick Saunders. Burial will follow at the Lewisville Cemetery. Visitation will be from 5-8 p.m. on Tuesday June 21 at the Marshall & Erlewein Funeral Home, Lewisville.