The Explainer General
Where am I? This was a cruel question for sailors before John Harrison.
In 1707 a fleet of British warships mistook their location and sailed onto the rocky Scilly Islands. Two thousand men drowned. The Royal Navy offered a prize of £20,000 (3 to 4 million dollars in today’s money) for anyone who could provide a way for ships to find their position.
North and south latitude wasn’t the problem. Tables gave the positions of the sun, moon and stars above or below the equator. Navigators could use a sextant (it measures angles between the ocean horizon and a celestial body) to find a ship’s position north or south. But the only way of knowing your position on the spinning earth, east or west, is to know what time it is, within seconds, at the Royal Observatory at Greenwich, England—0° longitude.
Sailors needed a seagoing clock!
Clocks in the 1700’s were slow or fast by several minutes a week. Not good enough. And they measured seconds with a pendulum, which wouldn’t work on a rocking, rolling ship.
John Harrison was a fine carpenter who became fascinated by accurate timekeeping. He built big clocks for houses, barns and churches. Bit by bit he made them more accurate. He set out to win the longitude prize.
He invented ways for a clock to compensate for temperature, so they wouldn’t run slower when it got warmer. He invented a nearly frictionless escapement (the mechanism that “counts” the tick-tocks with the clock’s hands). He overcame the pendulum problem with pivoted “dumbells” that rocked back and forth with springs.
Harrison worked for five years to construct the large and beautiful Sea Clock #1. In 1736 Harrison and his clock took a trip on HMS Centurion to Lisbon, Portugal, and back. Harrison was terribly seasick. His clock was not. It was a great success.
But the Royal Navy wouldn’t award the prize. It dithered for the next 37 years. Harrison worked on, making his sea clocks smaller and more accurate. In 1761 he sent his son William on a trial run with Sea Watch #1 to Jamaica and back. The smaller clock worked beautifully. The Navy kept dithering.
Not until Harrison was 80 years old was part of the prize awarded to him. He died three years later but he knew that he had changed the world, solving one of our most important, most perplexing problems: where are we?
An important part of Jan Adkins' considerable output is books of non-fiction for young people, his special audience. He also writes humor and feature articles for several magazines. He has illustrated most of his books and contributes illustrations to dozens of mainstream magazines, especially on marine and technical subjects. Have a look at his Wooden Ship: The Building of a Wooden Sailing Vessel in 1870, a chronicle of a fictional whale ship describing and illustrating the details of her building from design to launching.
Jan Adkins is a member of iNK's Authors on Call and is available for classroom programs through Field Trip Zoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more.
MLA 8 Citation
Adkins, Jan. "Tick Tock: A Carpenter Solves an Ocean Riddle." Nonfiction Minute,
iNK Think Tank, 19 Mar. 2018, www.nonfictionminute.org/
Stories About Regular Folks Doing Remarkable Things
I learned about the Caterpillar Club when I interviewed some flying WASPs—not the kind that buzz around on tiny wings. These WASPs were airplane pilots, the first women to fly for the United States military. They served during World War II: the Women Airforce Service Pilots (or WASP, for short).
The Caterpillar Club they told me about was named for silkworm caterpillars that helped save pilots’ lives. If a plane developed engine trouble in midair, pilots could float to safety by using a parachute made from silk, a lightweight cloth that silkworm caterpillars help create. These caterpillars use a spit-like substance in their mouths to spin a long silk thread that they wrap around themselves, forming a cocoon that they live in for several weeks until they become moths. Those long silk threads can then be unwound from the cocoons and woven together to make silk cloth.
About twenty years before World War II, a parachute company started the Caterpillar Club for people whose lives were saved by using a parachute to escape from a disabled plane. People could write to the company about their parachute rescue, pay a membership fee, and the company would send them a little caterpillar pin.
However, the WASP pilots I spoke with said that some pilots liked to feel they were part of the Caterpillar Club even if it wasn’t an aircraft’s fault that led them to use a parachute. During World War II, pilots—both men and women—trained to fly military aircraft for the Army in small open planes. The planes didn’t have a roof. If a nervous pilot-in-training forgot to buckle the seat belt and the plane tipped over, the pilot could fall out! Fortunately, they always wore a parachute. Landing safely—thanks to the parachute—not only let them feel part of the Caterpillar Club, but also helped the students remember to never, ever forget to buckle up again.
However, by World War II, many parachutes used by U.S. pilots weren’t made of silk. The silk-producing areas of the world were controlled then by Japan, which the U.S. was fighting in this war. Because U.S. companies could no longer get silk cloth, they began making parachutes from a new material scientists had just invented—nylon. Most parachutes are made of nylon today. Even so, the Caterpillar Club lives on.
Click here for source notes on this article.
If you are interested in finding out more about the WASPs, Amy Nathan has written a book on the subject. Through firsthand accounts, she tells how these early pilots they test-flew newly repaired aircraft, dragged banners behind their planes so male trainees could practice shooting moving targets with live ammunition (!), and ferried all kinds of aircraft from factories to military bases.
Yankee Doodle Gals will give you a new look at World War II and show you just how dramatically society has changed since then. Click here for more information.
MLA 8 Citation
Nathan, Amy. "Caterpillars to the Rescue." Nonfiction Minute, iNK Think Tank, 20
Mar. 2018, www.nonfictionminute.org/the-nonfiction-minute/
Are you tougher than a tardigrade? I don’t think so.
These typically water-dwelling animals may be microscopic in size (barely half of a millimeter when fully grown!), but boy are they fierce. Sometimes called “water bears,” they’re anything but cuddly. Each of their eight legs is decked out with wicked claws. Some tardigrades have full body armor. Most have specialized "sucker" mouths to pierce the cells of plants and animals and suck out their nutrients, while others prefer to consume their tiny prey whole… and that prey might even be another tardigrade!
Aside from ending up as someone else’s dinner, though, tardigrades are practically indestructible. They can survive in just about any conditions and take on just about anything life has in store for them. Starvation? No worries there: Tardigrades can go without food for at least 10 years. What about water, you say? No problem. They’ll just suspend their life activities and wait until the drought is over. They can survive at pressures more than six times that of the deepest ocean trenches. And, you’d die from radiation poisoning long before a tardigrade would even notice. Scientists have even tried shooting them into outer space… and the tardigrades survived.
Because of their ability to live practically anywhere, these little guys are practically everywhere. Tardigrades can be found on top of Mount Everest and in boiling hot springs, in desert dunes and rainforest canopies, in freshwater lakes and salty oceans, on your roof, outside your front door… maybe even in your bed or on your dinner plate! There are billions and billions of tardigrades… and they’re always making more!
Fortunately, there’s no need to worry—tardigrades are completely harmless to humans. In fact, tardigrades may actually end up being our best friends someday. Because they can do so many things that other Earthly animals can’t, scientists are studying tardigrades to try to find solutions to all kinds of problems. Want to dry something out to preserve it, then rehydrate it later? Study how tardigrades do it. Wish we could safely reanimate something that has been frozen? Learn from the tardigrades. Need to protect cells from being damaged by radiation? Figure out why tardigrade cells can withstand it.
Who knows? Someday the tough tardigrades might teach us all kinds of handy tricks!
Tardigrades are short and plump, with four pairs of legs, each with four to eight claws also known as "disks." Schokraie E, Warnken U, Hotz-Wagenblatt A, Grohme MA, Hengherr S, et al. (2012)/Wikimedia Commons
An adult Milnesium tardigrade, an example of more than 1,000 species of the tiny animal. Bob Goldstein and Vicky Madden, UNC Chapel Hill/Wikimedia Common
This video shows a tardigrade in real time at 100X magnification. Dmitry Brant via Wikimedia Commons
Laurie Ann Thompson and coauthor Ammi-Joan Paquette begin a fascinating new series with Two Truths and a Lie, a book that presents some of the most crazy-but-true stories about the living world. Some of the stories are too crazy to be true—and readers are asked to separate facts from fakes! "A brief but savvy guide to responsible research methods adds further luster to this crowd pleaser.” —ALA Booklist (starred review)
MLA 8 Citation
Thompson, Laurie Ann. "Tardigrades Make the Grade." Nonfiction Minute, iNK Think
Tank, 21 Mar. 2018, www.nonfictionminute.org/the-nonfiction-minute/
Celebrating the History of Science
and the Science behind History
A common punishment for those accused of a crime in seventeenth century Europe was to be sent to the galleys. That meant spending the rest of your life at an oar in the dark, stinking hold of a ship.
Wind and oars were the only known propellant of the age. Paid employment at the oar had been tried and dismissed. The only reliable way to produce the necessary speed and endurance to chase down (or escape from) enemy ships or Barbary pirates was to use the whip on your oarsmen, something that didn’t go over well with paid employees. But as condemned criminals were plentiful in that era, it wasn’t difficult to find oarsmen.
When in 1685 Louis XIV revoked the Edict of Nantes—a law passed by his grandfather Henry IV that had ensured the freedom of Protestant worship in France—many French Protestants (known as Huguenots) who tried to flee the country were sent to the galleys.
What was life like as a galley slave? We know something about it from letters and memoirs of Huguenot convicts.
After a long and often grueling march to the ports, the convicts would be sorted into groups of five—these would become the people with whom one would eat, sleep, and work, often until one died of old age or overwork or both. Each group of five men manned an eighteen-foot oar–and there might be fifty oars on a ship. The convicts remained chained to their places. With each stroke, they had to rise together and push the oar forward, and then dip it in the water and pull backward, dropping into a sitting position. During battle, rowers might be required to maintain full speed for twenty-four hours straight, and be fed biscuits soaked in wine without pausing in their exertions. Those who died—or lost consciousness—were thrown overboard.
Horrific, yes. But there were at least some brief respites from the wretched existence, periods of time when the wind’s sails propelled the ship and the rowers could rest. And when the ship overwintered in port, the life of a gallérien became almost tolerable. They had room to lie down and sleep. Many gallériens learned to knit, and others were already skilled wig makers, tailors, and musicians—and were allowed to employ their trades in rotating weeks ashore.
In his memoirs, a Huguenot named Jean Marteilhe wrote about his capture in 1701 as a boy of 17, and his experiences as a galley slave having been chained together with other deserters, thieves, smugglers, Turks and Calvinists for 6 years from 1707 to 1713. His account is entitled Memoirs of a Galley Slave of the Sun King.
Sara Albee's book Why'd They Wear That? is published by National Geographic. Get ready to chuckle your way through centuries of fashion dos and don'ts! In this humorous and approachable narrative, you will learn about outrageous, politically-perilous, funky, disgusting, regrettable, and life-threatening creations people have worn throughout the course of human history, all the way up to the present day. For more information, click here.
MLA 8 Citation
Albee, Sarah. "Row, Row, Row Your Boats." Nonfiction Minute, iNK Think Tank, 22
Mar. 2018, www.nonfictionminute.org/the-nonfiction-minute/
The “Julia Child” of kids’ hands-on science
No one wants to mess with someone who is super strong! Even if you’re undersized, especially if you’re undersized, you’ve got to try the two tricks in this Minute .
Here’s the first challenge: Bet another person can’t remove your hand from the top of your head. The challenge-taker must try to remove your hand according to your rules. Otherwise, it’s cheating. Sit on the floor. Place your hand with your fingers spread apart firmly on the top of your head. Have your friend grasp your lower arm next to your elbow. Now let him/her pull upward, trying to lift your hand from the top of your head.
Chances are excellent that you’ll be lifted off the ground before your palm parts from its perch.
Why is this so? If you’ve studied simple machines you may have learned about a mechanical advantage. That’s how a simple machine such as a lever can multiply your strength or speed. In this case, you’re putting your friend at a mechanical disadvantage. Your arm is a lever. In order to move your hand from the top of your head, you need an upward force near your hand. If that force is delivered as far away from your hand as possible, it loses its power. It’s easy to remove your hand if you deliver an upward force near your wrist. But at your elbow? No way! Got it?
Here’s another trick with the secret sauce of physics. Bet you can keep ten people from shoving you into a wall. Place your hands against a wall with your fingers spread and your arms outstretched. Have ten people line up behind you, hands on the shoulders of the person in front of them. At the count of three, have everyone push on the person in front of them as hard as they can. I mean, really lean in.
You, hero of the day, can hold them all off and not bend your elbows.
Why? Actually, each person absorbs the force of the person behind them so that you are not experiencing the cumulative force of ten people, only the force of the person directly behind you. So pick someone smaller than you to be that first person. If you’re not super strong, you can still be super smart.
If you don’t want to try this yourself, look at my videos of other people doing the challenges. Maybe you’ll change your mind.
If you like these bets, check out Vicki Cobb’s new release of We Dare You! You might want to join her We Dare You! National Video Project and make more videos yourself from her book. Learn more about it here.
Vicki Cobb is a member of iNK’s Authors on Call. You can invite her to your class through the magic of videoconferencing. Learn more about it here.
MLA 8 Citation
Cobb, Vicki. "How to Make Your Friends Think You're Super Strong." Nonfiction
Minute, iNK Think Tank, 23 Mar. 2018, www.nonfictionminute.org/
We give 'em reading that gets 'em talking!
Learn from many voices....
For Vicki Cobb's BLOG (nonfiction book reviews, info on education, more), click here: Vicki's Blog
The NCSS-CBC Notable Social Studies Committee is pleased to inform you
that 30 People Who Changed the World has been selected for Notable Social Studies Trade Books for Young People 2018, a cooperative project of the National Council for the Social Studies (NCSS) & the Children’s Book Council