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Chloe Effron

Why Does it Rain?

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Chloe Effron

WHY? is our attempt to answer all the questions every little kid asks. Do you have a question? Send it to

All around you, in the air you breathe, water hangs out in the sky in a form called vapor (VAY-purr). The amount of water vapor in the sky is called humidity (hu-MID-it-ee). Every cloud in the sky is made from this vapor, from the big white fluffy ones to the dark gray heavy ones. These are the ones that rain.

Warm air can hold more water vapor than cold air. Warm air also rises, or goes up. And cold air can push warm air up. As these tiny drops of water fly high into the sky, they gather together in clumps and form clouds. 

When enough of this water vapor gathers together in a cloud and then cools down, it gets very heavy and forms droplets called condensation (CON-den-SAY-shun). This is when gravity takes over. Gravity is the force that holds you, your house, and all the animals onto the Earth so we don’t float off into space. With clouds, gravity pulls the water droplets out of the sky, and they fall as rain. If the air is cold enough, those raindrops can become ice crystals. Then they fall as snow, sleet, or hail instead of rain. 

To learn more about rain, visit Easy Science for Kids. 

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Lucas Adams
7 Things You Didn’t Know About the Revolutionary War
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Lucas Adams

In Lafayette in the Somewhat United States, Sarah Vowell—author, historian, and public radio darling—explains how a gutsy French teenager named Lafayette became a key player in America’s War of Independence. Along the way, Vowell spills all sorts of incredible history, from the time George Washington saved a British general’s dog to why a New Jersey town is named for a traitor. Her book is full of hilarious, strange, and tragic details. Here are just a few that stuck with us.


After humiliating defeats at Brandywine and Germantown in 1777, much of the Continental Congress had lost faith in General Washington’s military abilities. One vocal critic was Founding Father Benjamin Rush, who wrote an anonymous letter to Patrick “Give Me Liberty, Or Give Me Death” Henry that Washington should be replaced. Rush wanted Horatio Gates or Thomas Conway—two men who’d distinguished themselves in battle—for the job instead.

Conway seemed like an especially good choice, since he had a bone to pick with Washington. After showing bravery at the Battle of Brandywine, the cocky junior officer asked Washington for a promotion. But the general refused, arguing that others needed to be promoted first. Disgruntled, Conway took his complaint to the Continental Congress, where he threatened to resign. The squeaky wheel routine worked; he walked away with a promotion and a new title: Inspector General of the Army. Washington remained unimpressed: “General Conway’s merit ... and his importance to this Army, exist more in his own imagination than in reality.” But now that Conway had the backing of the Continental Congress, he decided to take aim at Washington. The new Inspector General wrote to Horatio Gates, also a general, urging him to take a run at the top job.

When Washington caught word of the letter, he confronted Conway and Gates, both of whom backed down quickly. Lafayette was one of the few revolutionaries that stood by Washington during the conspiracy, and the young Frenchman branded Conway as “an ambitious and dangerous man.” But the plot—if it really was one—fizzled quickly. While there were surely plenty of whispers, just how big the conspiracy against Washington truly was is difficult to tell. Vowell points out, “some of the conspirators covered their tracks later on, after George Washington became George Washington.”

General Gates, who’d built his reputation on winning at Saratoga, was soon tarnished by a major defeat at the Battle of Camden in South Carolina. Conway resigned from the Continental Army in April 1778, but continued to badmouth the Commander-in-Chief until the upstart was shot in the face in a duel. His opponent, a Washington admirer, noted: “I have stopped the damned rascal’s lying tongue at any rate.” Conway survived, and died in exile in France in 1800—but not before he’d written Washington a note of apology for the whole affair.  


After a Patriot defeat at the Battle of Brandywine, Washington hoped to turn the tide with a nighttime assault on British troops—but it didn’t work. The Battle of Germantown was another disaster: 150 of Washington’s men were killed, 500 wounded, and 400 taken prisoner.

But Washington didn’t lose his sense of good manners with the battle. After the fight, a fox terrier with British General William Howe’s name on its tag showed up in the Patriots’ camp. In keeping with the etiquette of the times, Washington promptly returned the pup to the commander with a note (likely written by Alexander Hamilton, Washington’s aide-de-camp at the time):

To General William Howe

[Perkiomen, Pa.] Octr 6. 1777

General Washington’s compliments to General Howe. He does himself the pleasure to return [to] him a dog, which accidentally fell into his hands, and by the inscription on the collar appears to belong to General Howe.


Now famous for its closed lanes and political intrigue, Fort Lee, New Jersey, is also intriguing for its name, which it owes to a surprisingly devious figure: Charles Lee, a general in the Continental Army.

The English-born Lee fought in the Seven Years War, worked as aide de camp for the King of Poland, and was even married to a Mohawk woman. (His Mohawk name was “Boiling Water,” a reference to his hot temper.) After he failed to obtain a commission in the British military, Lee settled in America in 1773, and volunteered for service in the Continental Army when the fighting broke out.

Though he had far more military experience, Lee was passed over for Commander-in-Chief in favor of Washington. Perhaps in an attempt to soothe Lee’s ego, Washington had Fort Lee named after him in 1776. Soon after, though, Lee was captured by the British at a tavern in New Jersey, a few miles from his troops.

While in British custody, Lee committed treason, advising William Howe on the best way to seize Philadelphia. After a prisoner swap in May 1778, Lee was back with the Continental Army, but he didn’t last long: At the Battle of Monmouth in June, after a single volley of fire with the British, Lee ordered his men to retreat from the field, much to Washington’s fury. Washington chewed him out publicly, and Lee was court-martialed in July; by 1780, Lee had been dismissed from the army.

As Vowell points out, name swaps were common during the shifting moments of the war: “Fort [Benedict] Arnold became Fort Clinton and then West Point,” so it’s a strange oversight that Fort Lee is still Fort Lee. But it turns out Fort Lee isn’t the only vestige of Charles Lee’s legacy: Lee, Massachusetts, Lee, New Hampshire, and Leetown, West Virginia are all named after him. Of course, perhaps some of that can be forgiven since Lee’s treason was only discovered in 1857, when William Howe’s papers were made public.


Henry Knox’s family was in the shipping business. But when the Boston-based firm closed shop in 1759, he needed to look for new work—so he became an apprentice at the bookstore Wharton & Bowes. By 1771, he’d saved up his money to open up his own shop, The London Book Store.

Knox took to bookselling, and The London was quite a success. He also took to revolution: After witnessing the Boston Massacre in 1770, Knox used his free time to read up on warcraft. He studied books on military tactics and fortification construction, taught himself math to learn how to better target artillery, and he even quizzed soldiers who visited his shop to learn more about war. By 1772, he’d joined a local militia, the Boston Grenadiers.

Following the Boston Tea Party, the British Parliament passed the Intolerable Acts, including the Boston Port Act, which sealed the harbor off from trade. Cut off from his book shipments, Knox’s financial situation grew dire. As fighting broke out in Lexington and Concord, Knox and his wife snuck across the river to Cambridge to join up with revolutionary forces. Oddly enough, it didn’t take long for Knox to catch the eye of George Washington, who was impressed with Knox’s homemade fortifications. Very soon, Knox was appointed Chief Artillery Officer.

Knox’s book smarts were instrumental to the Patriot troops throughout the war, from moving artillery in the dead of winter, to aiding in the final victory at Yorktown leading to his appointment as the first-ever Secretary of War for the new nation.


Once the fighting had ended in America, Lafayette returned to France. There, the young commander found his homeland in the middle of a revolution. In 1789, Lafayette witnessed the storming of the notorious Bastille prison and subsequently became the leader of the newly-formed Paris National Guard, which oversaw the prison, among other things. The group was given the main key to the Bastille, and Lafayette decided to regift it to Washington. But he had to get it to him first.

The key, along with a drawing of the Bastille being demolished, was handed off to Common Sense author Thomas Paine. Paine, however, was unable to make the full trip to America, so he handed the key over to South Carolina Representative John Rutledge, Jr., adding his own gift of some cast steel razors into the box for Washington. After exhibitions in New York and Philadelphia, the key ended up in Washington’s house at Mount Vernon, where Lafayette saw it again in his visit to America in 1824.


As head of the Paris National Guard, one of Lafayette’s charges was to safeguard the Royal family (from 1791 to 1792, France was officially a constitutional monarchy). But in 1792, the radical wing of the revolution took over, the king was dethroned, and even the brilliant Marquis de Lafayette could no longer pull off being both a revolutionary and a nobleman. Facing imprisonment and likely execution as an enemy of the state, Lafayette fled France in 1792. He had hoped to catch a boat to America from a Dutch port city, but he was caught by Austrian troops who controlled the Netherlands first.

While he was lying in an Austrian prison, Lafayette’s wife, Adrienne, was placed under house arrest along with his daughter. They were then moved to a prison. They were the lucky ones in the family: Adrienne’s mother, grandmother, and sister were all executed during the Committee of Public Safety’s Reign of Terror. But in 1794, at the height of the Terror, James Monroe became the new nation’s Minister to France. Monroe and his wife, Elizabeth, were intent on insuring Adrienne’s safety. The couple knew they had to tread carefully.

To draw attention to Adrienne’s plight, they bought a carriage, and Elizabeth rode it to the prison Adrienne was held in. She attracted a crowd along the way, curious to see who she was visiting. When Elizabeth arrived at the prison, she embraced Adrienne in public, who was obviously relieved the carriage was not there to take her to her execution.

The crowd’s emotional response helped convince the Committee of Public Safety to grant Adrienne’s freedom, and she and her daughter traveled to Austria to be with Lafayette.


In the fall of 1824, Lafayette decided to visit his American friends again—his first return trip since his revolutionary days. On New Year’s Day in 1825, Congress feted Lafayette at a dinner held in his honor. At the event, Lafayette returned the kind words and gestures with a toast: “The perpetual union of the United States: It has always saved us in time of storm; one day it will save the World.”

Vowell gave Lafayette’s prophecy a mixed review: “Whether or not the United States has saved the world, it did save France a time or two.”

But nearly a century after Lafayette toasted the power of the nation he helped to birth, Charles E. Stanton—nephew of Lincoln's Secretary of War, Edwin Stanton—took the Frenchman’s vision seriously. When Stanton arrived in France as an aide to General Pershing during World War I, he went to Lafayette’s grave and said:  “Lafayette, we are here.”

To buy Sarah Vowell’s incredible book, click here.

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Lucas Adams
7 Things You Probably Didn’t Know About Rats
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Lucas Adams

Most people think rats are gross. Filthy and unwanted, they’re known for carrying diseases and sometimes giant pieces of pizza. But Robert Sullivan thinks differently: in 2004, Sullivan published a masterpiece on the critters, Rats: Observations on the History and Habitat of the City’s Most Unwanted Inhabitants. In it, Sullivan spends a year staking out alley rats, interviewing rat catchers, and digging through the critters’ contribution to history from housing reform to entertainment. Here are seven short facts we can’t stop thinking about from Sullivan’s incredible book.


Rats are thigmophilic (touch loving). As Sullivan points out, it’s why they feel most comfortable in corners, where they can feel up against a wall while scouting for an escape route. As they weave their way through trash-strewn alleyways, stumble through pipes, and flee across kitchen floors, rats “develop a muscle memory” of the spaces, and the best ways to get to their destination. Oddly enough, this knowledge is passed on when a rat dies: In Sullivan’s words, “Deep in their rat tendons, rats know history.” Younger rats follow the lead of older rats and learn these routes for themselves, preserving the pathways to food and safety for another rat generation.


According to Sullivan, subway workers in New York call the rats that live in stations and hop around the rails “track rabbits.”


Decked out in a top hat and sash decorated with cast-iron rats, Jack Black was an early pioneer of rat catching. Black dubbed himself the official rat catcher of Queen Victoria, even though he never had a royal decree from her—though he did once sell her some rats. While Black spent most of his time catching the critters, he also collected them and sold them to Victorian women as pets. Queen Victoria was one of his clients, as was children’s book author (and scientist) Beatrix Potter. Black was an equal-opportunity seller. Some of his rats went to rat pits (see below). Meanwhile, others became some of the earliest lab rats, including a specimen of albino rats he sold to scientists in France. As Sullivan theorizes: “I like to think that all the great scientific achievements that have been made in the modern scientific era as a result of work with laboratory rats are ultimately the result of the work of Jack Black, rat catcher.”


When rats were spotted on the southeastern border of Alberta, Canada, in 1950, the Canadian government sprung into action with an intensive rat-control program. The Alberta agricultural department told Sullivan the program has kept Alberta “an essentially rat-free province.” Still, there have been moments when the rats have made inroads, as Sullivan notes: “Alberta did have rats in its border areas for a brief period, and at that time, one Alberta mayor refused to believe it. He stated that he would eat any rats found in his town.” He had a change of heart, however, when “presented with a bushel full of Rattus norvegicus.”


In the 1830s (well before The Bachelor was the cruelest spectacle the public could stomach), rat fighting was all the rage. Onlookers would bet how long it would take for a dog to kill a group of rats. One of New York City’s biggest pits was owned by Kit Burns, an Irish immigrant linked to the infamous Dead Rabbits Gang. Burns operated his pit out of Sportsman’s Hall, located at 273 Water Street, where he had numerous dogs ready for the matches (“Jack” and “Hunky” were two of his favorites). Occasionally, Burns even subbed in ferrets. But he never crossed one line that other pits did: putting men in the ring.

By the late 1860s, rat pits were under fire. The founder of the Society for the Prevention of Cruelty to Animals, Henry Bergh, was pushing for raids across the city, and Sportsman’s Hall was one of the last operating rat pits. Before long, Kit started diversifying his income. He rented the bar out to prayer meetings in the morning, and then rented it out for three full years as The Kit Burns Mission, a home for “wayward women.”

But Burns didn’t exactly give up rat fighting: 10 years later, he and the crowd at his new bar The Band-Box were busted for a rat fight on November 21, 1870. He died of a cold before he could be brought to trial. As for Bergh and others pushing back against animal cruelty, it’s thanks to their work that rat pit fights have faded both in popularity and from memory.


You know James Audubon for his iconic The Birds of North America. But did you know that the guy who traveled across the early United States documenting its avian wildlife also had a thing for rats? He made this lithograph of Black Rats snacking on eggs in a barn. He also used his downtime to chase after them. When he was living in New York in 1839 he got the city's mayor to let him “shoot Rats at the Battery early in the morning, so as not to expose the inhabitants in the vicinity to danger…” Turns out, in addition to being one of America’s foremost naturalists, Audubon was also considerate to his neighbors.


Sullivan speaks highly of Pest Control Technology magazine throughout Rats: He attends one of their “Rat Management Summits” and reads columns in the magazine by rat control legend Bobby Corrigan, author of the industry standard Rodent Control: A Practical Guide for Pest Management Professionals. The magazine’s website features a regular podcast interviewing pest catching pros, and also, occasionally, poetry.

For more on Sullivan’s wonderful book, be sure to click here.


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