The Explainer General
She was 15 pounds below minimum weight for the Navy when she joined, but she had a mighty mind. Admiral Grace Hopper changed the Navy. And your world.
She graduated from Vassar College in math and physics then took a doctorate from Yale in math. She joined the Navy in World War II because it needed mathematicians to build the massive machines that computed tables of distance, gun elevation, projectile weight, windage and other factors for precise naval gunnery. Almost immediately she saw something other mathematicians didn’t see: computers could talk.
They weren’t just number crunchers to Grace. They could do much, much more if they were given a simple language that would bring the advantages of gigantic computing power and enormous data storage to common uses.
While working on the early computers she developed a “compiler,” a kind of translating machine that turned plain-language needs into a set of mathematical commands that retrieved number data from storage banks, performed thousands or millions of math operations, and provided real-world answers.
In 1959 she was crucial in devising the first broad-based computer language, COBOL (COmmon Business Oriented Language). It is the root of the many computer operating systems we use today.
Then-Captain Grace worked with the National Bureau of Standards to develop self-testing capabilities so a computer could “de-bug” itself. She coined this word when she extracted a fried moth disrupting one of her computers.
She led the Navy away from a few giant computers to interconnected, smaller, scattered computers, opening the door to the internet. You are reading plain language words from my small computer on your web-connected small computer. Thank you, Grace.
In 1985, at 79, she was promoted to rear admiral of the United States Navy Reserve. She said, “The most important thing I've accomplished, other than building the compiler, is training young people. They come to me, you know, and say, 'Do you think we can do this?' I say, ‘Try it.’ And I back 'em up. They need that. I keep track of them as they get older and I stir 'em up at intervals so they don't forget to take chances.” She died in 1992 at 85.
Admiral Grace Hopper received many awards and decorations but the Navy’s most sincere tribute came in 1996 when it named the guided missile cruiser DDG-70, USS Hopper. Naturally, its sailors call their ship “Amazing Grace.”
Jan Adkins successfully tackles the art and science of 10,000 years of bridge building and imparts a lot of historical drama along the way. The process is given fascinating life in this accessible study, wonderfully illustrated by Jan Adkins himself. Ranging from ancient Rome to the present day, from simple log bridges to marvels of industrial technology, and from well-known landmarks to little-known feats of engineering and art, this book gives readers a new appreciation for that most familiar of structures, the bridge.
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. "Amazing Grace." Nonfiction Minute, iNK Think Tank, 25 Jan. 2018,
The Explainer General
Most disasters are a cascade: small failures and minor circumstances, one leading to another, blossom into a cataclysm. On January 16, 1919, a cascade of tremendous size was poised above Boston’s North End.
The weather was one factor: unusually warm for winter.
Purity Distilling Company fermented and distilled molasses to make rum and alcohol. The 18th Amendment to the United States Constitution, prohibiting sales of alcoholic beverages, was due to be passed the very next day. This may have prompted Purity to collect as much molasses as possible.
The enormous tank holding the molasses was about 50 feet tall and 90 feet in diameter, holding 2,300,000 gallons. It was poorly built of thin steel painted brown to hide its leaks. Local families often collected some of the dripping molasses to sweeten their food. The unseasonably warm temperature quickly rose from 2° F (-16.7° C) to 40° F (4.4° C), expanding the liquid, and natural fermentation produced CO2 increasing tank pressure.
Just after noon, North End families felt the ground shake and heard a sound like a machine gun— the tank’s rivets popping out. The big tank exploded, sending a 25-foot wall of molasses roaring down the hill toward Commercial Street at about 35 miles an hour. In front of the molasses went a blast of air that blew some folks off their porches and tumbled others along the street like rag dolls. Homes and buildings were destroyed, smashed from their foundations. Horses pulling wagons were swept away. The steel girders of the Boston Elevated Railway were buckled, knocking a rail-car off the tracks.
Twenty-one people were killed and more than a hundred were injured. Many were saved by Massachusetts Maritime Academy cadets who rushed off their docked training vessel and plunged into the brown goo to rescue people. It’s difficult to know how many dogs, cats and horses died.
As you can imagine, the clean-up was awful. Firehoses from hydrants and harbor fireboats washed away as much as possible. Boston Harbor was brown for months. Sightseers tracked the goo back to homes, into hotels, onto pay-phones and onto doorknobs. Everything Bostonians touched was sticky for months.
Some say that on a hot summer day along the North End’s docks, the sickly sweet smell of molasses lingers. Bostonians can smile at the Great Molasses Flood now, but in January of 1919, that cascade of disasters was deadly serious.
Jan Adkins is an author, an illustrator, and a superb storyteller. Read about him on his Amazon page. He is also 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. "The Great Boston Molasses Flood: How Can a Tragedy Sound Funny?"
Nonfiction Minute, iNK Think Tank, 19 Jan. 2018,
David M. Schwartz
The amazing, engaging, math exponent
Imagine Earth as a button. I don’t mean you’re going to sew it onto your shirt. But imagine the planet Earth shrunk to the size of a button. (Of course Earth is not flat like a button but we’re giving our shrunken Earth the same diameter as a shirt button.)
Go ahead and draw a circle around a shirt button. Call it “Earth.” Suppose you wanted to draw Jupiter, the largest planet, at the same scale as this micro-Earth. That means you’re going to shrink it to the same fraction of its original size as our button-Earth. What size would little Jupiter be?
One way to find out would be to calculate how many times bigger the real Jupiter is than the real Earth. Earth’s diameter is about 8,000 miles (13,000 kilometers). Jupiter’s is about 88,000 miles (143,000 km). Divide the size of Jupiter by the size of Earth to see that Jupiter is about 11 times bigger.
So, since Jupiter’s diameter is 11 times that of Earth’s, put 11 buttons in a line to show the diameter of Jupiter. Then draw the circle that represents Jupiter. If you don’t have 11 buttons, just look at the picture. Did you think the Earth was a big place? Look at it compared with Jupiter!
But what about the sun? The sun’s diameter is about 865,000 miles (1,400,000 km). That means it’s almost 10 times bigger than Jupiter. Can you find a way to draw a circle 10 times the size of our Jupiter? We’ve drawn part of it for you, on the same scale as our button-sized Earth. On the picture, it’s labeled “our arc.” (An arc is part of a circle.) Looking at the arc, you can imagine the rest of the circle and compare the sun to Jupiter and Earth. A minute ago, you thought Jupiter was big. Now it looks shrimpy compared to the sun!
But is the sun really gigantic? Do some research to find out the size of a red giant star like the strangely named Betelguese (pronounced “beetle-juice.”) Figure out what it looks like compared to our sun, which is a medium-sized star. You may be amazed at the difference. And you thought the sun was big!
Is anything truly big? Is anything truly small? Or does that depend on what it’s being compared to?
Both images are by Marissa Moss, the illustrator of David M Schwartz's book, G is for Googol.
G is for Googol: A Math Alphabet Book is a wonder-filled romp through the world of mathematics.
For more information, click here.
David Schwartz 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.
Schwartz, David M. "If the Earth Were a Button." Nonfiction Minute, iNK Think
Tank, 16 Jan. 2018, www.nonfictionminute.org/the-nonfiction-minute/
David M. Schwartz
The amazing, engaging, math exponent.
Think of a big number. How about one million? It's a thousand thousand. That's a lot. If you counted nonstop to a million, it would take you about 23 days.
A million is small compared to a billion, which is a thousand million. Want to count that high? You'll be at it for 95 years. But a trillion makes a billion look puny. A trillion is a thousand billion (or a million million). Counting that high would take you 200,000 years. Have fun!
Of course trillion is not the biggest number. There's quadrillion, quintillion, sextillion, septillion, octillion, nonillion, decillion and more. Each is a thousand of the previous one. There's even a humongous number called vigintillion, a one with 63 zeros.
But vigintillion is a shrimp compared to a googol. Googol? Notice how it's spelled: G-O-O-G-O-L, not G-O-O-G-L-E. The number googol is a one with a hundred zeros. It got its name from a nine-year old boy. A googol is more than all the hairs in the world. It's more than all the grass blades and all the grains of sand. It's even more than the number of atoms in the universe. Astrophysicists estimate the number of atoms to be a one with 82 zeros. You'd need to add 18 more zeros to get to a googol.
Incidentally, a few years ago, the two men who had invented a powerful new internet search engine decided to name their website and company for the gigantic number googol. But they spelled it wrong. That's why the company Google is spelled with an L-E. But the number googol is still spelled with an O-L.
Googol is so large that it's practically useless, but the boy who named it came up with a name for an even bigger number, "googolplex." A googolplex is a one with a googol zeros. There isn't enough ink in all the pens of the world to write that many zeros but feel free to give it a try.
So is googolplex is the biggest number? What about a googolplex and one? Two googolplex? A googolplex googolplex? Any number you say, I can say one bigger.
I hear you asking, "What about infinity? Isn't that the biggest number?" Sorry, but infinity isn't a number. A number specifies an amount and infinity is no amount. It means "goes on and on forever."
And that's what numbers do. They go on and on forever. Infinity is not a number but numbers are infinite.
Think you're too old for an alphabet book? You'll think again if you check out a sampling from David M. Schwartz's: B is for Binary, F is for Fibonacci, P is for Probability... You can see that this is an ABC book unlike any other. For more information, click here.
David Schwartz is a member of iNK's Authors on Call and is available for classroom programs through FieldTripZoom, a terrific technology that requires only a computer, wifi, and a webcam. Click here to find out more
MLA 8 Citation
Schwartz, David M. "What's the Biggest Number?" Nonfiction Minute, iNK Think Tank, 1 Dec. 2017, www.nonfictionminute.org/ Whats-the-Biggest-Number.
David M. Schwartz
The amazing, engaging, math exponent
Do you want to be a lot older? Here’s how: state your age in seconds instead of years!
Ready to do some math? But what math will you do?
First you have to design a problem-solving strategy. There are many approaches but for all of them, consider that with every passing second, you are a second older. So your age is a moving target. Best to pick a specific time of day and find your age in seconds at that time today.
It doesn’t really matter what time of day you pick. If you can find out from your birth certificate what time of day you were born, you could select that time today for your target. If you were born at 4:14pm, you will find out how old you are (in seconds) at 4:14pm today.
Or just pick any time today and pretend you were born at that time.
What next? I hope you will try out your own approach but here is a simple strategy that would work:
Step 1. How many days old are you? Figure out how many days elapsed between the day you were born and your most recent birthday. There are 365 days in a year, not counting leap years. In your lifetime, every year divisible by 4 was a leap year and it had a 366th day, which was February 29th. So add an extra day for each February 29th you’ve lived through.
Then figure out how many days have passed since your last birthday. Try to find a way to make this job quicker than counting each day. Look at calendars as you do this to find shortcuts.
Now you have your age in days. It’s already looking like a big number, isn’t it? Just wait!
Step 2. How many seconds are in a day? Think about how to figure this out. You know how many seconds are in a minute (60) and how many minutes are in an hour (60) and how many hours are in a day (24). So how many seconds are in a day? Multiply 60 X 60 X 24. Bet you didn’t realize a day was so long!
Step 3 So what’s Step 3? You now know how many days you have lived and how many seconds are in a day, so what do you do next? Again, multiply!
Next time someone tells you you’re not old enough to do something, you can tell him or her, “Oh yes I am. I’m 299,592,620. That’s what I was at 11:30 this morning. Now I’m even older!”
Good luck with that!
A is for “abacus,” B is for “binary,” C is for “cubit”
and W is for “When are we ever gonna use
this stuff, anyway?” David M. Schwartz's G is for Googol: A Math Alphabet Book is a wonder-filled romp through the world of mathematics. For more information, click here.
David 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.
Schwartz, David. "How Old Are You...in Seconds?" Nonfiction Minute, iNK Think
Tank, 3 May 2018, www.nonfictionminute.org/the-nonfiction-minute/