Why Does It Rain?

Chloe Effron
Chloe Effron

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

All around you, in the air you breathe and in the sky above you, water hangs out in a form called vapor (VAY-purr). The amount of water vapor in the air 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. 

Wayfair’s Fourth of July Clearance Sale Takes Up to 60 Percent Off Grills and Outdoor Furniture

Wayfair/Weber
Wayfair/Weber

This Fourth of July, Wayfair is making sure you can turn your backyard into an oasis while keeping your bank account intact with a clearance sale that features savings of up to 60 percent on essentials like chairs, hammocks, games, and grills. Take a look at some of the highlights below.

Outdoor Furniture

Brisbane bench from Wayfair
Brisbane/Wayfair

- Jericho 9-Foot Market Umbrella $92 (Save 15 percent)
- Woodstock Patio Chairs (Set of Two) $310 (Save 54 percent)
- Brisbane Wooden Storage Bench $243 (Save 62 percent)
- Kordell Nine-Piece Rattan Sectional Seating Group with Cushions $1800 (Save 27 percent)
- Nelsonville 12-Piece Multiple Chairs Seating Group $1860 (Save 56 percent)
- Collingswood Three-Piece Seating Group with Cushions $410 (Save 33 percent)

Grills and Accessories

Dyna-Glo electric smoker.
Dyna-Glo/Wayfair

- Spirit® II E-310 Gas Grill $479 (Save 17 percent)
- Portable Three-Burner Propane Gas Grill $104 (Save 20 percent)
- Digital Bluetooth Electric Smoker $224 (Save 25 percent)
- Cuisinart Grilling Tool Set $38 (Save 5 percent)

Outdoor games

American flag cornhole game.
GoSports

- American Flag Cornhole Board $57 (Save 19 percent)
- Giant Four in a Row Game $30 (Save 6 percent)
- Giant Jenga Game $119 (Save 30 percent)

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Map Shows How Everyone Blamed Syphilis on Everyone Else

Portrait of Gerard de Lairesse by Rembrandt van Rijn. De Lairesse, a painter and art theorist, had congenital syphilis that deformed his face and eventually blinded him.
Portrait of Gerard de Lairesse by Rembrandt van Rijn. De Lairesse, a painter and art theorist, had congenital syphilis that deformed his face and eventually blinded him.
Gerard de Lairesse, Wikimedia Commons // Public Domain

The origins of syphilis may be one of the greatest (and grossest) health mysteries of our time. Some historians claim that Christopher Columbus and his sailors contracted the sexually transmitted disease in the New World and brought it back to Europe. Other experts believe that the disease, which is caused by the bacterium Treponema pallidum, existed in various forms around the globe but was simply misclassified as other conditions. (European writers, including Italian historian Niccolo Squillaci, first described syphilis in the late 15th century.) And in 2015, researchers announced that they had identified signs of congenital syphilis in 14th-century skeletons from St. Polten, Austria, adding new evidence to an ages-old debate.

One thing's for sure: As the map below illustrates, nobody wanted to take credit for originating the virulent condition. Created by Redditor masiakasaurus (and spotted by The A.V. Club), the map illustrates the various nicknames Europeans gave the disease before the name syphilis caught on. (Italian physician and poet Hieronymus Fracastorius coined the word in 1530 with his poem "Syphilis Sive Morbus Gallicus" ("Syphilis or the French Disease"). Not surprisingly, nearly every single moniker used for the disease places blame on another group for giving birth to what by then had become a continental scourge.

“Most physicians felt that this was a new disease, that it hadn’t been seen before in Europe, and that view tended to prevail for quite some time,” medical historian John Parascandola told The Atlantic in 2016. “There were certain tempting reasons for people to accept that—blame it on the others, blame it on the outsiders. Before that, the French were blaming it on the Italians, the Italians were blaming it on the French, et cetera.”

Masiakasaurus sourced the syphilis nicknames from nine scholarly books/journals, including The Early History of Syphilis: A Reappraisal,The rise and fall of sexually transmitted diseases in Sweden, and A Medical History of Persia and the Eastern Caliphate: From the Earliest Times Until the Year A.D. 1932. You can view the full list on Reddit—after giving silent thanks to Alexander Fleming for discovering penicillin, found to be an effective cure for syphilis in 1943.

[h/t The A.V. Club]