When the Continental Congress convened in 1775 in Philadelphia, Thomas Jefferson and John Adams became fast friends. The tall, lanky Virginian and stocky Massachusetts native worked together to draft the Declaration of Independence and spent time together as diplomats for the new United States in Europe. Their relationship frayed, however, when Jefferson succeeded Adams as president in 1801. On opposite sides of the Republican and Federalist divide, the two men remained estranged until 1812, when Adams sent Jefferson a New Year’s greeting. Their reconciliation spawned a remarkable correspondence that lasted for nearly 15 years. On July 4, 1826, as the country celebrated 50 years since declaring its independence from Great Britain, the 83-year-old Jefferson passed away at his Virginia estate, Monticello. The 90-year-old Adams, on his own deathbed in Quincy, Massachusetts, and unaware of his friend’s death, whispered a few last (sadly mistaken) words: “Thomas Jefferson survives.”

History added a postscript to this remarkable coincidence in 1831 when James Monroe became the third of the first five U.S. presidents to die on Independence Day. James Madison, Jefferson’s close friend and fellow Virginian who succeeded him in the White House, died on June 28, 1836, after refusing stimulants offered by his doctors in order to prolong his life until July 4.

Unlike his now-notorious brother, Edwin Booth was a devoted supporter of the Union during the Civil War—but he also had a more personal connection to the martyred President Abraham Lincoln. In late 1864, Lincoln’s son Robert Todd was traveling via train from New York to Washington, D.C. During a stop in Jersey City, New Jersey, he stepped back on the crowded platform to let others pass by, pressing his back against a stopped train. When the train began to move, Lincoln fell onto the tracks and would have been gravely injured—or worse—if a stranger hadn’t caught him by the collar and hauled him back onto the platform. As he later wrote, Lincoln immediately recognized his savior as the famous stage actor Edwin Booth and thanked him. For his part, Booth only later learned the identity of the man he had rescued. His friend Adam Badeau, a colonel in the Union Army, wrote the actor to congratulate him for saving the president’s son, who by then was serving as Badeau’s fellow officer on General Ulysses S. Grant’s staff.

Less than a month after sitting at his father’s deathbed in April 1865, Robert Todd Lincoln resigned his U.S. Army commission and moved to Chicago with his distraught mother. He later married, had children and established a successful law practice. He also remained active in politics, accepting the post of secretary of war in the administration of President James A. Garfield in 1881. That July, Lincoln was at the railroad station in Washington, ready to travel to New Jersey with Garfield, who had been in office less than two months at the time. Before their train left the station, however, a deranged, disgruntled office-seeker named Charles Guiteau shot Garfield in the back; the president died of complications from the wound two months later.

In 1901, President William McKinley invited Lincoln to Buffalo, New York to attend the Pan-American Exposition. Lincoln arrived while the event was already in progress and was heading to meet the president when the anarchist Leon Czolgosz fatally shot McKinley in the chest and abdomen in front of a crowd of well-wishers. Lincoln, who in the latter part of his career served as president of the Pullman Company, was said to have wryly remarked that there was “a certain fatality about the presidential function when I am present.”

In the summer of 1861, Wilmer McLean and his family were living on his wife’s plantation near Manassas Junction, Virginia. As Union forces approached, Confederate General P.G.T. Beauregard took over the farm as his headquarters. On July 21, 1861, Confederate and Union troops clashed in the first major battle of the Civil War along the small stream known as Bull Run, which ran through McLean’s property. A second major battle—the Second Battle of Bull Run—took place on the same ground in August 1862.

By the end of 1863, McLean and his family had relocated to the small hamlet of Appomattox Court House, some 120 miles southwest of Manassas Junction. McLean, who supplied sugar to the Confederate Army, was in Appomattox on April 9, 1865, when Confederate Colonel Charles Marshal approached him for assistance finding a suitable place to host a meeting between General Robert E. Lee and his Union counterpart, Ulysses S. Grant. That afternoon, Lee surrendered his Army of Northern Virginia to Grant in McLean’s parlor, which Union troops later stripped for mementos of the historic occasion. McLean put the “Surrender House” on the market a year later. He wanted to return to Manassas, which he did in 1867, though he never sold the Appomattox house. Instead, he defaulted on the property, and it was sold at public auction in 1869. Now operated by the National Park Service, the McLean Home opened to the public in 1949.

The periodic comet known as Halley’s Comet returns to Earth’s vicinity about every 75 years, give or take a bit due to the gravitational pull of the planets it passes. Back in the 18th century, English astronomer Edmond Halley concluded that reports of a comet appearing in 1531, 1607 and 1682 actually referred to the same comet returning in periodic intervals; he predicted the comet’s reappearance in 1758 (though he died before the prediction came true). Halley’s Comet was in the skies again when the celebrated author Samuel Langhorne Clemens, better known as Mark Twain, was born on November 30, 1835, in Florida, Missouri. By 1909, 74 years had passed, and Twain offered a prediction that his own death would—like his birth—coincide with the comet’s appearance. He was quoted as saying: “It will be the greatest disappointment of my life if I don’t go out with Halley’s Comet. The Almighty has said, no doubt: ‘Now here are these two unaccountable freaks; they came in together, they must go out together’.”

As it happened, Twain died of a heart attack on April 21, 1910—the day after Halley’s Comet emerged from the far side of the Sun. The comet’s appearance proved particularly spectacular that year for other reasons as well: It passed only about 13.9 million miles (22.4 million km) from Earth, or about 1/15 the distance between Earth and the Sun; and for the first time, the comet’s passage was captured on camera. Halley’s Comet appeared most recently in 1986 and is scheduled to enter our skies again in 2061.

Born in Argentina to Irish immigrants, Jessop left convent school back in Britain after her mother, a stewardess on the Royal Mail Line, became ill. To provide for her family, the 21-year-old became a ship stewardess as well, working on the Royal Mail Line before moving on to the White Star Line. Locked in competition with Cunard for the transatlantic passenger market, White Star launched its trio of gigantic luxury liners, the Olympic, the Titanic and the Britannic, in 1911. Jessop was serving aboard the Olympic that September, during its fifth commercial voyage, when the liner collided with the HMS Hawke near the Isle of Wight, in southern England. (It was later determined that suction from the Olympic had pulled the Hawke directly into the ocean liner.) Jessop then made the move to the Titanic in time for the “unsinkable” ship’s maiden voyage in April 1912, when it sailed out of Southampton en route to New York City. She later wrote in her memoirs of the unforgettable night of April 14-15, when the ship hit an iceberg and sank, taking some 1,500 people along with it. Jessop helped other women and children into lifeboats before climbing into one herself; one of the ship’s officers placed a bundled-up baby on her lap. After eight hours on the lifeboat, a ship called the Carpathia rescued Jessop and the others, and a frantic woman (whom Jessop assumed was the baby’s mother) snatched the infant from her arms.

The third White Star ship, the Britannic, was requisitioned as a hospital ship after World War I broke out. Remarkably, Jessop—by then a nurse in the British Red Cross—was serving aboard the Britannic in November 1916, when the ship struck a mine planted by a German U-boat in the Aegean Sea. Though the explosion caused extensive damage, and the Britannic sank less than an hour later, only 30 people died. More than 1,000 others were saved—including “Miss Unsinkable” herself. Jessop continued working on cruise ships after the war, eventually compiling a 42-year career at sea before her retirement. She died in 1971.