Question: Peter Folger's grandson was known for inventing what?

Context articles: W. B. Hibbs and Company Building
Macro Manuscript
Benjamin Franklin
Shooting Star Tommy Gun
Peter Folger
Dering Manuscript
Peter Folger (Nantucket settler)
Adam Albert von Neipperg
Eli Whitney
Joseph P. Folger

The W. B. Hibbs and Company Building, also known as the Folger Building, is an historic structure located at 725 15th Street, Northwest, Washington, D.C., in Downtown Washington, D.C.
The Macro Manuscript is a collection of three 15th-century English morality plays, known as the "Macro plays" or "Macro moralities": "Mankind", "The Castle of Perseverance", and "Wisdom".
 So named for its 18th-century owner Reverend (1683–1767), the manuscript contains the earliest complete examples of English morality plays.
 A stage plan attached to "The Castle of Perseverance" is also the earliest known staging diagram in England.
 The manuscript is the only source for "The Castle of Perseverance" and "Mankind" and the only complete source for "Wisdom".
 The Macro Manuscript is a part of the collection at the Folger Shakespeare Library in Washington, D.C. (MS. V.a. 354).
 For centuries, scholars have studied the Macro Manuscript for insights into medieval drama.
 As Clifford Davidson writes in "Visualizing the Moral Life", "in spite of the fact that the plays in the manuscript are neither written by a single scribe nor even attributed to a single date, they collectively provide our most important source for understanding the fifteenth century English morality play."
Benjamin Franklin FRS, FRSE (January 17, 1706 [O.S. January 6, 1705] April 17, 1790) was one of the Founding Fathers of the United States.
 Franklin was a renowned polymath and a leading author, printer, political theorist, politician, freemason, postmaster, scientist, inventor, humorist, civic activist, statesman, and diplomat.
 As a scientist, he was a major figure in the American Enlightenment and the history of physics for his discoveries and theories regarding electricity.
 As an inventor, he is known for the lightning rod, bifocals, and the Franklin stove, among other inventions.
 He facilitated many civic organizations, including Philadelphia's fire department and the University of Pennsylvania, an Ivy League institution.
The Shooting Star Tommy Gun is a pneumatic machine gun manufactured by Shooting Star Inc.
 It was invented by Charles A. Feltman, the grandson of Charles Feltman, often credited as the inventor of the hot dog in Coney Island, New York with young Feltman previously inventing a hot dog roll toaster.
Peter Folger (December 26, 1905 – August 27, 1980) was an American coffee heir, socialite, and member of the prominent United States Folger family.
 He was also the longtime chairman of the board and president of the Folgers Coffee Company.
 He was the grandson of founder J. A. Folger, and the father of Abigail Folger, who was murdered in 1969 at the age of 25.
The Dering Manuscript is the earliest extant manuscript text of any play by William Shakespeare.
 The manuscript combines "Part 1" and "Part 2" of "Henry IV" into a single-play redaction.
 Scholarly consensus indicates that the manuscript was revised in the early 17th century by Sir Edward Dering, a man known for his interest in literature and theater.
 Dering prepared his redaction for an amateur performance starring friends and family at Surrenden Manor, Kent, where the manuscript was discovered in 1844.
 This is the earliest known instance of an amateur production of Shakespeare in England.
 Sourced from the 1613 fifth quarto of "Part 1" and the 1600 first quarto of "Part 2", the Dering Manuscript contains many textual differences from published quarto and folio editions of the plays.
 Dering cut nearly 3000 lines of Shakespearian text (including significant abridgment of the character of Falstaff) and added some 50 lines of his own invention along with numerous minor interventions.
 The Dering Manuscript is currently a part of the collection at the Folger Shakespeare Library in Washington, DC (Folger MS V.b.34).
Peter Folger or Foulger (1617 –1690) was a poet and an interpreter of the American Indian language for the first settlers of Nantucket.
 He was instrumental in the colonization of Nantucket Island in the Massachusetts colony.
 He was the grandfather of Benjamin Franklin.
Adam Albert, Count von Neipperg (8 April 1775 – 22 February 1829) was an Austrian general and statesman.
 He was the son of a diplomat famous for inventing a letter-copying machine, and the grandson of Count Wilhelm Reinhard von Neipperg.
Eli Whitney (December 8, 1765 – January 8, 1825) was an American inventor best known for inventing the cotton gin.
 This was one of the key inventions of the Industrial Revolution and shaped the economy of the Antebellum South.
 Whitney's invention made upland short cotton into a profitable crop, which strengthened the economic foundation of slavery in the United States.
 Despite the social and economic impact of his invention, Whitney lost many profits in legal battles over patent infringement for the cotton gin.
 Thereafter, he turned his attention into securing contracts with the government in the manufacture of muskets for the newly formed United States Army.
 He continued making arms and inventing until his death in 1825.
Joseph P. Folger is professor of communication at Temple University.
 Together with Robert A. Baruch Bush, he is the originator, and best known advocate, of the transformative model of mediation.