It's about one-four-thousand-five-hundredth as long as World War I.
In other words, 8.40 hours is 0.000219 times the length of World War I, and the length of World War I is 4,570 times that amount.(a.k.a. First World War, a.k.a. Great War, a.k.a. World War, a.k.a. War to End All Wars, a.k.a. WWI, a.k.a. WW1) (1914 - 1918)
World War I is considered to have begun with the assassination of Austrian Archduke Franz Ferdinand on June 28th, 1914 and to have lasted until the signing of the armistice with Germany on November 11th, 1918, for a total of 38,300 hours. However, the Treaty of Versailles which ended conflicts between the major powers was not signed until June 28th, 1919 and the last formal peace treaties were not signed until August 23rd, 1923 — 41,900 hours after the armistice was signed.
It's about one-six-thousand-five-hundredth as long as World War II.
In other words, 8.40 hours is 0.0001596 times the length of World War II, and the length of World War II is 6,266 times that amount.(a.k.a. Second World War, a.k.a. WWII, a.k.a. WW2) (1939 - 1945)
The most widespread war in history, the Second World War is generally considered to have started with the German invasion of Poland on September 1st, 1939 and to have until the surrender of Japan on September 2nd, 1945, a total of 52,630 hours. Also the deadliest conflict in history, the war had an estimated 60 million casualties globally.
It's about one-six-thousand-five-hundredth as long as The Construction of the Chunnel.
In other words, the length of The Construction of the Chunnel is 6,667 times 8.40 hours.(a.k.a. Channel Tunnel, a.k.a. Le tunnel sous la Manche) (1987 thru 1994) (Folkstone, Kent, UK to Coquelles, Pas-de-Calais, France)
The construction crew of the Chunnel broke ground in England on December 15th, 1987 and the tunnel was inaugurated by the Queen of England and the President of France on May 6th, 1994 — a total construction time of 55,940 hours. The 4.9 million cubic meters of chalk excavated from the UK side of the Chunnel was dumped within sea walls to create the 299,467.38 sq. km (74 acre) Samphire Hoe County Park near Dover, Kent.
It's about one-eight-thousand-five-hundredth as long as The Revolutionary War (American).
In other words, 8.40 hours is 0.0001144 times the length of The Revolutionary War (American), and the length of The Revolutionary War (American) is 8,741 times that amount.(a.k.a. American War of Independence) (1775-83)
The War between Great Britain and the its thirteen colonies in North America (now the United States) for the independence of the United States is generally considered to have started with the Battle of Lexington and Concord on April 18th, 1775 (sometimes known as "The Shot Heard 'round the World") and to have concluded with the signing of the Treaty of Paris on September 3rd, 1783 — 73,440 hours. A total of 25,000 Americans are estimated to have died as a result of the war.
It's about one-ten-thousandth as long as King Tut's reign.
In other words, the length of King Tut's reign is 10,000 times 8.40 hours.(a.k.a. Tutankhamun, a.k.a. Tutankhaten, a.k.a. tVwa:t-ʕa:nəx-ʔaˡma:n) (1333 BCE - 1324 BCE)
Pharaoh of the 18th dynasty, Tutankhamun begin his reign at the age of eight in 1333 BCE and remained pharaoh until 1324 BCE — 80,000 hours later. When artifacts from Tut's tomb were on display at the Metropolitan Museum of Art (New York City, New York) from late 1976 to 1979, they were viewed by an estimated 8 million people.
It's about one-fifteen-thousandth as long as FDR's Presidential Term.
In other words, 8.40 hours is 0.000079140 times the length of FDR's Presidential Term, and the length of FDR's Presidential Term is 12,640 times that amount.(a.k.a. Franklin Roosevelt, a.k.a. Franklin Delano Roosevelt) (1933-45)
FDR, the 32nd President of the United States, served from March 4th, 1933 to April 12th, 1945, dying after 106,100 hours in office. At the time of his sudden death, Elizabeth Shoumatoff was painting a portrait of Roosevelt which, never finished, now hangs in a museum at the site of Roosevelt's Presidential retreat in Georgia.
It's about 15,000 times as long as The First movie.
In other words, 8.40 hours is 14,300 times the length of The First movie, and the length of The First movie is 0.00006990 times that amount.(1888) (Roundhay Garden Scene, National Museum of Photography, Film, and Television restored copy)
Filmed in 1888 by Louis Aimé Augustin Le Prince, Roundhay Garden Scene is the oldest surviving motion picture with a total running time of 0.000586 hours.