Question: Ken Babbs known for his participaction in the Acit Tests was a cohort and follower of an American author in what year?

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9175 Graun: 9175 Graun, provisional designation 1990 OO, is a stony Eunomian asteroid from the central region of the asteroid belt, approximately 10 kilometers in diameter.  It was discovered on 29 July 1990, by American astronomer Henry E. Holt at Palomar Observatory in California, United States.  The asteroid was later named for American author and amateur astronomer Ken Graun.

Louis Heilprin: Louis Heilprin (1851–1912) was a Hungarian American author, historian, and encyclopedia editor.  He was born in Miskolc, Hungary in 1851.  His father, Michael, son of Phineas Mendel, was also an encyclopedist and scholar of Hebrew history and literature and a follower of Lajos Kossuth.  He had a younger brother Angelo who was a professor at the Philadelphia Academy of Sciences and two sisters.  The family left Hungary as refugees in 1856.  Heilprin was educated by his father.

That Evening Sun: "That Evening Sun" is a short story by the American author William Faulkner, published in 1931 on the collection "These 13", which included Faulkner's most anthologized story, "A Rose for Emily".  The story was originally published, in a slightly different form, as "That Evening Sun Go Down" in "The American Mercury" in March of the same year.  "That Evening Sun" is a dark portrait of white Southerners' indifference to the crippling fears of one of their black employees, Nancy.  The story is narrated by Quentin Compson, one of Faulkner's most memorable characters, and concerns the reactions of him and his two siblings, Caddy and Jason, to an adult world that they do not fully understand.  The black washerwoman, Nancy Mannigoe, fears that her common-law husband Jesus is seeking to murder her because she is pregnant with a white man's child.  The title is thought to be taken from the song Saint Louis Blues, originally composed by W.C. Handy, but popularized by Bessie Smith and Louis Armstrong in 1927.  Faulkner first came across Handy's music when the latter played dances in Oxford, Mississippi.  Though the song is never explicitly referenced in the text, Faulkner employs a number of blues tropes to structure the plot and develop racial stereotypes.  Scholar Ken Bennett notes that "the image of the 'evening sun' is a common one in black religious music.  For example, the spiritual 'It's Gettin' Late Over in the Evenin', the Sun Most Down,' based on Revelation 20, uses the image of the evening sun to suggest the coming of death and judgment."

Ken Babbs: Ken Babbs (born January 14, 1936) is a famous Merry Prankster who became one of the psychedelic leaders of the 1960s.  He along with best friend and Prankster leader, Ken Kesey wrote the book "Last Go Round".  Babbs is best known for his participation in the Acid Tests and on the bus "Furthur".

Ken Kalfus: Ken Kalfus (born April 9, 1954 in New York City) is an American author and journalist.  Three of his books have been named "New York Times" Notable Books of the Year.

Ken Barlow (harness racing): Kenneth D. Barlow (born July 28, 1936) professionally known as Ken Barlow, was an American Harness Horse Driver.  Ken Barlow married Sharlene Ryle on July 2, 1955 and they had four daughters Debbie, Dianne, Donna, and Darlene.  His professional career began in 1960 with a horse named Lucky Jim and he won his first race with a horse named Tommy Goose.  Ken Barlow was a two time Champion and Winner of the “Indiana Harness Horse Driver of the Year” award in 1964 and 1965.  He started racing a horse named Virgne’s Lady Plaid in 1965, who in 1966 won "Indiana's 3 year old Trotting Crown" by winning 13 straight victories and “Indiana Horse of the Year” with 21 out of 30 wins overall.  That same year they tied for the “National Lead in Harness Horse Race Wins by a Trotter”and set the seasons record of 2:06.4 on a half mile track at Anderson Indiana.  On April 19, 1968 Ken Barlow and Virgnes Lady Plaid set the season record at Saratoga Raceway of 2:05.1 and then lowered it to 2:04.3 on April 26 and then lowered it again to 2:03.4 on May 10, 1968.

Merry Pranksters: The Merry Pranksters were cohorts and followers of American author Ken Kesey in 1964.

John Taffin: John August Taffin (born May 2, 1939) is an American author from Boise, Idaho who writes several columns for gun magazines including "Guns", "Gun Digest", "Sixgunner", "Shoot!"  and "American Handgunner".  A former math teacher from 1964-1995, Taffin is regarded as an authority on single-action revolvers, handloading, handgun hunting, big-bore revolvers, and metallic silhouette shooting.  Taffin has authored five books and over 500 published articles.  His monthly published gun columns include: Siluetas, Campfire Tales, The Sixgunner, and Taffin Tests.

Acid Tests: The Acid Tests were a series of parties held by author Ken Kesey in the San Francisco Bay Area during the mid-1960s, centered entirely on the use of, and advocacy of, the psychedelic drug LSD, also known as "acid".  LSD-25 had not been made illegal in California until October 6th,1966.

Clement Finch: Clement Alfred Finch (July 4, 1915 – June 28, 2010), often deemed “The Iron Man”, was a Physician specializing in Hematology whose research on iron metabolization in the bloodstream at the University of Washington led to significant advancements in accurately diagnosing and treating anemia during a time period in which little was known about this aspect of the body.  Finch was distinctively noted for using himself as a test subject by taking blood and bone marrow from his own bones before conducting similar tests on patients.  He graduated in 1941 from the University of Rochester Medical School and a year later was married to the first of three wives.  He experienced a 60-year tenure at the University of Washington, and has published many scholarly articles pertaining to iron in the bloodstream and is the author of three books entitled: Iron Metabolism (1962) Red Cell Manual (1969) and Fulfilling the Dream: A History of the University of Washington School of Medicine 1946 to 1988 (1990).  Clement Finch was elected as a Fellow of the National Academy of Sciences in 1974, and elected as a Fellow of the American Academy of Arts and Sciences in 1976.

Supporting paragraphs: Ken Babbs Merry Pranksters
Answer: 1964