May 30 – Tongue Tied

One of the best things about science is how it corrects mistakes. And one of the worst things about popular culture is how it perpetuates them. Today, Daniel, Peter, and Mary discover the truth behind a popular science myth when they get tongue tied!

 

 

It was a bright, sunny Saturday afternoon and life was just about perfect. Daniel had come to visit Mary and Peter that morning and they’d spent several hours experimenting with kites, trying to discover what sort of tail made a kite fly best. What they had discovered was that the person flying the kite was even more important than the tail. Peter’s kites always flew into trees or crashed into the ground. Mary could keep her kites flying but had a very hard time launching them. But Daniel was a natural kite-flyer and could make even the most unlikely of kites soar high above.

To make the day even better, when they’d gotten back to Mary’s back yard, they found that her father had set up a picnic for them, complete with hot dogs, potato salad, three kinds of pickles, and fresh watermelon. The three friends enthusiastically munched through the piles of food, only slowing down once they reached the slices of watermelon.

“Pass the salt, please,” Mary asked.

“I still don’t get it,” Daniel said as he salted his slice of watermelon and then passed her the condiment. “How can adding salt to watermelon make it taste so good?”

“Dunno,” Peter said. “It just does.”

“Is that any kind of attitude for a scientist to display?” Mary’s father chided gently. “A real scientist would try to figure it out.”

“OK, how do we do that?” Peter replied.

“In science, you always start with what you know. What do we know about taste?”

“Well, last year Mrs. Krabapple had us map our tongues with four tastes,” Mary said. “So we know that there are four different tastes and that they are in different parts of the tongue.”

“As a wise man once said, it isn’t what we know that causes us problem; it is what we think we know that really ain’t so,” her father sighed. “Your teacher was wrong on two counts. First, a taste isn’t found in just one part of your tongue. And second, there are more than four tastes.”

“Huh?” the three young scientists chorused.

“This is sort of like the myth that we only use 10% of our brains when we actually use the whole thing. What happened is that a reporter misheard something and told everyone about it.  The tongue story got started when a psychologist by the name of Boring had translated a German paper that showed different parts of the tongue were more sensitive to different tastes. For some reason, this got reported by the popular press as though those tastes could only be sensed in those parts of the tongue. But you can easily prove that this isn’t true,” Mary’s father said.

“How?” Daniel asked.

“Spoken like a true scientist!” Mary’s father beamed. “First, stick out your tongue and dry it off with a napkin. That will make it certain that the taste doesn’t get spread by the saliva in your mouth. Now take a piece of water melon and touch it to the different parts of your tongue – on the front, on each side, in the middle, and in the back. See how you can taste it all over your tongue?”

The three experimenters followed his directions and quickly discovered that he was right. As they finished their experiment, he continued.

“Now watermelon has a lot of sugar in it, so you were mainly tasting ‘sweet’. We can repeat the experiment with the other tastes if you like, but what it will prove is that you have taste buds for every taste on every part of your tongue. There are actually taste buds on your cheeks and in your throat as well.”

“Wow!” Peter said. “Mrs. Krabapple never said anything about that!”

“She may not have known,” Mary’s father replied. “Sadly, many teachers don’t get the support they need in order to teach science properly.”

“But what about the number of tastes?” Mary demanded. “You said that there aren’t four tastes.”

“That’s right,” her father replied. “Depending on how you want to count them, there may be as few as five or as many as thirteen different distinct tastes. The five tastes that just about everyone agrees on are sweet, sour, bitter, salty, and umami.”

“Ohh-what-si?” Daniel asked.

“‘Ooh-mommy’,” Mary’s father repeated. “It is sometimes called ‘savoriness’ or ‘meatiness’ because it is sort of like the taste of a good steak. Those hot dogs you three scarfed down had a lot of umami.”

“That’s pretty neat, but what do the different tastes have to do with why we like watermelon better with salt on it?” Peter asked.

“Ah, I think I’ll let you figure that out for yourselves. Stay here for a second!”

With that, Mary’s father went back into their kitchen. Mystified, the three young scientists looked at each other. From the kitchen, they heard a variety of cabinets being opened and closed and the clink of plates. After a few minutes, Mary’s father came back out carrying five different plates. As he put the plates on the table in front of them, he explained what the experiment would be.

“In each plate, we’ve got an example of a different taste. The first one has salt for saltiness. The second plate has baking cocoa for bitterness. The third plate has vinegar for sourness. the fourth plate has low-sodium soy sauce for meatiness. And the last plate has sugar for sweetness. And here are a bunch of water crackers; they don’t really have much in the way of flavor,” he paused as Peter grabbed a cracker and tasted it.

“Ugh!” Peter exclaimed. “It tastes like cardboard.”

“Right!” Mary’s father said. “Now here’s the experiment. First, you’ll dip a cracker into each of the different tastes and eat it. That will help you get familiar with the tastes. Then you’ll try dipping the cracker into two different tastes and then eat it. What do you think will happen?”

“Well, the two different tastes will just be two different tastes in our mouths,” Peter said. “Nothing will change.”

“I don’t know,” Daniel said. “Remember what happened when we added salt to the watermelon?”

“That’s right!” Mary exclaimed. “I’ll bet that the tastes change each other somehow.”

“Well, there’s only one way to be sure,” Mary’s father said. “Start tasting!”

What do you think will happen? Try the experiment yourself!

Intro

The three young scientists quickly grabbed crackers and dipped them into each of the plates. From their grimaces, it was clear that they didn’t much care for the tastes by themselves. But something changed when they started dipping the crackers into to tastes before eating them.

“Hey!” Peter excitedly said. “Did you guys try this? Sweet plus bitter – it tastes almost like a candy bar!”

“Cool!” Daniel replied. “I like sour and salty – it tastes like a pickle!”

“And salty plus umami is wonderful!” Mary added. “This is so delicious!”

“Can you figure out why it is so good,” Mary’s father asked. “You’ve definitely got enough information to form a hypothesis now.”

“Well, one taste by itself isn’t very good,” Peter said. “And it only hits one set of taste buds.”

“But two different tastes together are good, ” Mary said.

“And they hit two different sets of taste buds,” Daniel added. “So maybe the more different taste buds that get excited, the better the food tastes?”

“That’s right!” Mary’s father said. “That’s why the best recipes always have several different tastes in them. Cookies always have sweet and salty. Soda usually has sweet and sour. Soup has umami and salty. And so forth. Companies spend billions of dollars trying to find the perfect combination of different flavors. For example, what do you think would happen if you used umami with your watermelon instead of salty? Or if you used bitter?”

“I don’t know,” Peter started.

“But we sure want to find out!” Daniel and Mary chorused together. Smiling, the three scientists grabbed watermelon slices and began their most edible experiment of the day.

October 7 – The Straight Poop

Today’s factismal: Typhoid Mary killed at least three people and made another fifty-one ill, just by cooking without washing her hands.

The woman who would come to symbolize the need for effective medical laws was born 144 years ago today. Originally known as Mary Mallon, she would eventually come to be recognized the world over as “Typhoid Mary”, the very public face of a disease that was considered one of the world’s worst scourges.

Typhoid fever is a disease caused by bacteria that live in your gut. It lasts about a month and causes inflammation of your intestines (which isn’t nearly as much fun as it sounds like) along with a high fever, a slow heartbeat and bloody nose; during the later stages, it also causes diarrhea, which leads to dehydration and is the most common cause of death. For most of the sufferers, typhoid fever is a temporary inconvenience but it can be deadly. Every year, it infects an estimated 24 million people and kills about 200,000 people. Fortunately, the introduction of chlorination to the American water supply has reduced the local infection rate to near zero.

But back in 1900, there was no water in the water supply. Not that it would have done much good, as Mary didn’t believe in washing her hands. Not after she used the restroom and not before she started cooking. (I will now pause so you can all say “Eew!”). And, to make matters worse, Mary’s body had come to an arrangement with the bacteria that caused typhoid; they wouldn’t kill her and she wouldn’t worry about them. As a result, Mary was the perfect carrier. She’d start working for a family as a cook and then leave as soon as they all started getting ill. Over a period of seven years, she worked for ten families all of which had people come down with typhoid fever. When she was finally identified as the carrier by the local doctors, she refused to be treated for typhoid or to give up cooking. As a result, she was held as a “medical prisoner” for three years until she promised to stop working as a cook.

A lurid newspaper article about Typhoid Mary

A lurid newspaper article about Typhoid Mary

Of course, her promise lasted just long enough to get her out of isolation. Once she was free,s he started cooking again and people started getting sick again. As before, every time someone became ill, she’d quit and find a new job. Her continual job changes made it more difficult for the medical establishment to find her but they finally did in 1915. This time, she was confined for life. Though she was allowed visitors, they were forbidden to touch her or to accept so much as a glass of water from her hands for fear of spreading the disease. Her intransigence did have one good side-benefit; it forced the federal and state officials to recognize the danger that a carrier could pose to unsuspecting innocents. Thanks to her unwashed spree, there are now laws on the books of every state governing when and how a person can be held to prevent the spreading of a disease.

Of course, typhoid fever isn’t the only disease that can be spread by contaminated water. If you’d like to help scientists and medical practitioners by monitoring the water quality and purity in your neighborhood, then flow over to the World Water Monitoring Challenge:
http://www.wwmd.org/About.aspx

June 24 – Hug A Lug

Today’s factismal: The simplest way to improve your health is fun and free and right at your fingertips!

If you ask just about anyone what the simplest thing you can do to improve your health is, they’ll probably tell you “Eat better and exercise more”. And those things are good. Improving your diet can protect you from cancer, heart disease, and even Alzheimer’s. As for exercise, doctors have long known that if it were a pill, everyone would be taking it. Exercise improves your mood, gives you more energy, and can even make you look younger. But believe it or not, there is something that is even simpler to do that offers almost as many benefits as diet and exercise do. What is it? Hugging!

Hugs are good for every animal! (My camera)

Hugs are good for every animal!
(My camera)

That’s right – a simple hug each day can provide you with an amazing number of health benefits. It is no surprise that people who hug more often have better relationships with others (i.e., are more popular). What is a surprise is that they also have fewer colds than non-huggers do and may even help with weight loss by reducing levels of cortisol (the “stress hormone”). Not bad for something that is free and fulfilling, huh?

No word on if hugging dinosaurs improves your health (My camera)

No word on if hugging dinosaurs improves your health
(My camera)

Now if you want to participate in a citizen science project about hugs, it is pretty simple – so simple that no project is needed. Just look at the first ten people you meet and guess their mood. Are they happy? Bored? Distracted? Now offer hugs to the next ten people you meet. How did their mood change after the hug? And how did yours change? And if you’d like to keep track of how hugs help your symptoms, why not try Patients Like Me? This project connects people with health problems together so that they can learn from each other. To learn more, give your browser a big squeeze at:
https://www.patientslikeme.com/

June 20 – Tongue Tied

One of the best things about science is how it corrects mistakes. And one of the worst things about popular culture is how it perpetuates them. Today, Daniel, Peter, and Mary discover the truth behind a popular science myth when they get tongue tied!

 

 

It was a bright, sunny Saturday afternoon and life was just about perfect. Daniel had come to visit Mary and Peter that morning and they’d spent several hours experimenting with kites, trying to discover what sort of tail made a kite fly best. What they had discovered was that the person flying the kite was even more important than the tail. Peter’s kites always flew into trees or crashed into the ground. Mary could keep her kites flying but had a very hard time launching them. But Daniel was a natural kite-flyer and could make even the most unlikely of kites soar high above.

To make the day even better, when they’d gotten back to Mary’s back yard, they found that her father had set up a picnic for them, complete with hot dogs, potato salad, three kinds of pickles, and fresh watermelon. The three friends enthusiastically munched through the piles of food, only slowing down once they reached the slices of watermelon.

“Pass the salt, please,” Mary asked.

“I still don’t get it,” Daniel said as he salted his slice of watermelon and then passed her the condiment. “How can adding salt to watermelon make it taste so good?”

“Dunno,” Peter said. “It just does.”

“Is that any kind of attitude for a scientist to display?” Mary’s father chided gently. “A real scientist would try to figure it out.”

“OK, how do we do that?” Peter replied.

“In science, you always start with what you know. What do we know about taste?”

“Well, last year Mrs. Krabapple had us map our tongues with four tastes,” Mary said. “So we know that there are four different tastes and that they are in different parts of the tongue.”

“As a wise man once said, it isn’t what we know that causes us problem; it is what we think we know that really ain’t so,” her father said. “Your teacher was wrong on two counts. First, a taste isn’t found in just one part of your tongue. And second, there are more than four tastes.”

“Huh?” the three young scientists chorused.

“This is sort of like the myth of Brontosaurus which was really an Apatosaurus and the myth that we only use 10% of our brains when we actually use the whole thing. What happened is that a reporter misheard something and told everyone about it. What happened is that a psychologist by the name of Boring had translated a German paper that showed different parts of the tongue were more sensitive to different tastes. For some reason, this got reported by the popular press as though those tastes could only be sensed in those parts of the tongue. But you can easily prove that this isn’t true,” Mary’s father said.

“How?” Daniel asked.

“Spoken like a true scientist!” Mary’s father beamed. “First, stick out your tongue and dry it off with a napkin. That will make it certain that the taste doesn’t get spread by the saliva in your mouth. Now take a piece of water melon and touch it to the different parts of your tongue – on the front, on each side, in the middle, and in the back. See how you can taste it all over your tongue?”

The three experimenters followed his directions and quickly discovered that he was right. As they finished their experiment, he continued.

“Now watermelon has a lot of sugar in it, so you were mainly tasting ‘sweet’. We can repeat the experiment with the other tastes if you like, but what it will prove is that you have taste buds for every taste on every part of your tongue. There are actually taste buds on your cheeks and in your throat as well.”

“Wow!” Peter said. “Mrs. Krabapple never said anything about that!”

“She may not have known,” Mary’s father replied. “Sadly, many teachers don’t get the support they need in order to teach science properly.”

“But what about the number of tastes?” Mary demanded. “You said that there aren’t four tastes.”

“That’s right,” her father replied. “Depending on how you want to count them, there may be as few as five or as many as thirteen different distinct tastes. The five tastes that just about everyone agrees on are sweet, sour, bitter, salty, and umami.”

“Ohh-what-si?” Daniel asked.

“Umami,” Mary’s father repeated. “It is sometimes called ‘savoriness’ or ‘meatiness’ because it is sort of like the taste of a good steak. Those hot dogs you three scarfed down had a lot of umami.”

“That’s pretty neat, but what do the different tastes have to do with why we like watermelon better with salt on it?” Peter asked.

“Ah, I think I’ll let you figure that out for yourselves. Stay here for a second!”

With that, Mary’s father went back into their kitchen. Mystified, the three young scientists looked at each other. From the kitchen, they heard a variety of cabinets being opened and closed and the clink of plates. After a few minutes, Mary’s father came back out carrying five different plates. As he put the plates on the table in front of them, he explained what the experiment would be.

“In each plate, we’ve got an example of a different taste. The first one has salt for saltiness. The second plate has baking cocoa for bitterness. The third plate has vinegar for sourness. the fourth plate has low-sodium soy sauce for meatiness. And the last plate has sugar for sweetness. And here are a bunch of water crackers; they don’t really have much in the way of flavor,” he paused as Peter grabbed a cracker and tasted it.

“Ugh!” Peter exclaimed. “It tastes like cardboard.”

“Right!” Mary’s father said. “Now here’s the experiment. First, you’ll dip a cracker into each of the different tastes and eat it. That will help you get familiar with the tastes. Then you’ll try dipping the cracker into two different tastes and then eat it. What do you think will happen?”

“Well, the two different tastes will just be two different tastes in our mouths,” Peter said. “Nothing will change.”

“I don’t know,” Daniel said. “Remember what happened when we added salt to the watermelon?”

“That’s right!” Mary exclaimed. “I’ll bet that the tastes change each other somehow.”

“Well, there’s only one way to be sure,” Mary’s father said. “Start tasting!”

What do you think will happen? Try the experiment yourself!

 

 

 

 

 

The three young scientists quickly grabbed crackers and dipped them into each of the plates. From their grimaces, it was clear that they didn’t much care for the tastes by themselves. But something changed when they started dipping the crackers into to tastes before eating them.

“Hey!” Peter excitedly said. “Did you guys try this? Sweet plus bitter – it tastes almost like a candy bar!”

“Cool!” Daniel replied. “I like sour and salty – it tastes like a pickle!”

“And salty plus umami is wonderful!” Mary added. “This is so delicious!”

“Can you figure out why it is so good,” Mary’s father asked. “You’ve definitely got enough information to form a hypothesis now.”

“Well, one taste by itself isn’t very good,” Peter said. “And it only hits one set of taste buds.”

“But two different tastes together are good, ” Mary said.

“And they hit two different sets of taste buds,” Daniel added. “So maybe the more different taste buds that get excited, the better the food tastes?”

“That’s right!” Mary’s father said. “That’s why the best recipes always have several different tastes in them. Cookies always have sweet and salty. Soda usually has sweet and sour. Soup has umami and salty. And so forth. Companies spend billions of dollars trying to find the perfect combination of different flavors. For example, what do you think would happen if you used umami with your watermelon instead of salty? Or if you used bitter?”

“I don’t know,” Peter started.

“But we sure want to find out!” Daniel and Mary chorused together. Smiling, the three scientists grabbed watermelon slices and began their most edible experiment of the day.

June 13 – Round And Round

One of the best things about science is how an observation in one area can apply to something in a completely different area. Our friends Peter and Mary will discover that and much more in today’s episode of the Secret Science Society!

If you have a friend, then you know that the only thing more fun than having your friend come to your birthday party is getting to go to his. And the only thing more fun than that is getting to play with the goodies that you got at the party. And both Peter and Mary had been lucky at their friend Daniel’s party. Mary had won a toy car when they played charades and Peter was coming home with a helium balloon he won during the trivia contest. As they watched for their ride home, they played with their new prizes.

“Hey! There’s my mom!” Peter said.

“Thanks again for a great party, Daniel!” Mary said. Her father had brought the two of them to the party and she was going to ride back home with Peter; living next door had some advantages.

“Glad you could come,” Daniel said. As the new kid at school, he didn’t have many friends yet, but sharing experiments with Peter and Mary had already turned them into a close-knit group. “And thank you for the lab coat! I can’t wait to try it out! And the air cannon is great – I couldn’t believe it when it blew out my candles!”

“Glad you like it,” Peter and Mary chorused as they headed out the door and clambered into the car.

“Are you both buckled in?” Peter’s mother asked.

“Yes!” the two said, and the car pulled out. Mary put her toy car on the seat between her and Peter, and Peter let his balloon float in the air above his knees. As the car stopped at a stop sign, Mary suddenly grabbed for the toy car.

“Hey!” Mary exclaimed. “The car’s trying to escape!”

“Well, that beats being hit in the face by a balloon!” Peter replied. As the car sped away from the stop sign, Mary’s toy car rolled back and Peter’s balloon swung toward the front of the car.

“That’s weird,” he said. “My balloon goes the opposite direction of your car. I wonder why?”

“If you’ll wait until we get home,” Peter’s mother said, “I can show you. Even better, we can do an experiment to find out the answer.”

Since experiments were one of Mary and Peter’s favorite things to do, they cheerfully agreed. Almost as soon as the car stopped in Peter’s driveway, the two young scientists hopped out and looked expectantly at Peter’s mother.

“OK,” she laughed. “Let’s go do some science!”

Taking them into the kitchen, she gave each of them a raw egg.

“What does this have to do with balloons and toy cars?” Mary asked.

“You’ll see,” Peter’s mother replied. “What I want you to do is spin the egg as quickly as you can. Once it is spinning, put your hand on the egg for a second to stop the spinning and then take your hand off. What will happen?”

“The egg will just sit there,” Mary said.

“I don’t know,” Peter said. “It might act like the car somehow.”

“Well, there’s only one way to find out,” Peter’s mother said. “On the count of three, spin!”

What do you think will happen? Do the experiment!

 

 

 

 

 

“One, two three!”

Peter and Mary quickly spun their eggs. As soon as the eggs started to spin around, they put a hand on them and stopped the egg. Then they took their hands away and watched in amazement as the eggs started to spin again!

“Hey! What gives?” Mary asked.

“That egg is a lot like the inside of the car,” Peter’s mother replied. “Just as the car is a hard shell of steel filled with air, an egg is a hard shell of calcium carbonate filled with liquid. And both air and egg white and every other physical thing in the universe have something in common – they all have mass.”

“But that just makes things weigh a lot and keeps stuff on planets,” Peter objected. “It can’t make something spin after you stop it!”

“Actually it can,” his mother said. “You’re right that mass is what gives things weight. But mass also has another feature; it creates inertia – the tendency for something to keep moving in the direction it is going. When you spun the egg, you started the liquid inside spinning. And though you stopped the outside of the egg, you weren’t able to stop the liquid inside thanks to its inertia. So when you took your hand off of the egg, the liquid made it start spinning again.”

“But what if I used a hard boiled egg?” Mary asked.

“Then everything would be stuck together and the egg wouldn’t start spinning again; that’s one way to tell if you have a hard-boiled egg or a raw one,” Peter’s mother replied. “But the same thing happens in a car that happens in that egg. When the car started moving, inertia kept the stuff inside of it from going with it right away.”

“Is that why you get pushed back in the seat when my dad drives?” Mary asked.

“Yes; it takes a little time for the car’s cushions to give your body the same speed as the rest of the car and that’s what pushed you back. And that’s why your toy car rolled back when the car started moving forward – it didn’t have the same speed as the car and tried to stay in place. And when the car stopped, your toy car rolled forward; if you hadn’t caught it, then it would have had an accident.”

“So that’s why we wear seat belts!” Peter said. “They help hold you in place and keep you from moving forward when the car gets in an accident and stops suddenly.”

“Right,” his mother said. “So can you figure out why the balloon went the opposite way to the toy car?”

“The balloon must have been pushed by something, or its inertia would have kept it right above my knees,” Peter said.

“The air!” Mary exclaimed. “Your balloon is lighter than air! When the car starts up, the air gets pushed back by its inertia. Because the balloon is lighter than air, it gets pushed forward when the air moves back!”

“That’s exactly right! Well done!” Peter’s mother looked at the clock. “But it is getting late and Peter has enough inertia in the morning already – he doesn’t need any more!”

“OK! Thanks for the ride back home,” Mary said . “And thanks for the experiment!”

Smiling, she headed out the door and over to her house as her brain filled with ideas for using inertia.

 

 

June 6 – Rust Bucket

Spring brings many joys – flowers, soft breezes, and the first bicycle rides of the year. But what happens when you forgot to oil your bike before putting it away – and what does that have to do with the furnace that kept you warm all winter long? Join Peter and Daniel as they discover the answer in today’s Secret Science Society adventure!

 

There is little more frustrating than being forced to clean up your own mess. And there is nothing more necessary. So that’s what Peter was doing; with a wad of steel wool in one hand and a rusty bicycle chain in the other, he was trying to remove the rust that had spread like a fungus on his bike and kept him from being able to ride it. Peter was hard at work when he heard what sounded like a motorcycle pull up behind him. Turning around, he saw his friend Daniel stop on his new bicycle, complete with a playing card stuck in the spokes to make the motor sound.

“Hey, Peter!” Daniel said. “I thought we were going to go on a ride!”

“So did I, until I tried to ride my bike this morning,” Peter replied. “This dumb chain is all rusted and won’t turn properly. And you know my mom – ‘It’s your mess, so you get to clean it up!'”

“Well, that’s no fun. How about I help you so we can go riding? I still don’t know the area as well as you and Mary do,” said Daniel.

“Deal!”

The two boys started to work on opposite ends of the chain, flexing the links and scrubbing away the rust wherever it kept them from moving. When one of them had finished with a link, he’d squirt a little oil on it and move to the next one. As they worked, they talked. Naturally, the main topic was the problem of the rust.

“What happened?” Daniel asked. “Why did your chain rust up?”

“I don’t know,” Peter said. “The last time I rode it was when we went out right after that snowstorm in January.”

“That’s right,” Daniel said; “you wanted to see if you could make a bike ramp out of snow.”

“Yep. We piled all that snow up into a beautiful ramp and then I just smashed through it. I think it was because the snow trucks had already been by spreading salt on the roads. You know how mushy that makes snow.” At Daniel’s nod, he continued, “so I rode back to my house and left the bike in the garage. It was fine when I left it. I wonder why it rusted?”

“You just answered your own question,” a high, bright voice answered him. “You set your bike on fire and left it to burn.”

Turning around, the boys saw Peter’s mother in the door of the garage.

“I wanted to see how you were getting on with the bike,” she said. “But it looks as if you still don’t know how to keep this from happening again.”

“Yeah,” said Daniel. “Why did his bike rust when mine didn’t? I rode out there with him and put my bike back in my garage, just like he did.”

“Did you do anything before you put your bike away?” Peter’s mother asked.

“Yeah, I washed it down with water and then put oil on the chain and axles. ” Daniel turned to Peter and asked “Didn’t you do that?”

“No, that never made any sense to me. Why wash the bike? And why put oil on it afterward?”

“The answer to that is simple,” his mother replied. “But you’ll have to see it to understand it. Stay right there while I gather some supplies and we’ll do an experiment to show what happened to your bike.”

The boys sat up eagerly. Doing experiments was one of their favorite things and it would give them a break from the tedious chore of cleaning the bike. Just a moment later, Peter’s mother came out with a book of matches, a leftover candle from a birthday cake, and three pairs of sunglasses.

“What are the sunglasses for?” Peter asked.

“We’re going to do some chemistry,” his mother replied. “In a real lab, we’d have special safety goggles to keep the chemicals from getting into our eyes. We don’t have the safety goggles, but sunglasses are almost as good; they keep stuff from splashing into your eyes and are stylish to boot.”

She handed each of the boys a pair of sunglasses and put on her own set. Once they had all donned their sunglasses, she lit a match and used the flame to soften the bottom of the candle then mashed the candle down onto the concrete garage floor.

“There,” she said. “That will keep the candle in place for our experiment. When I strike a match, what do we get?”

“Fire,” chorused Daniel and Peter.

“And when I put the lit match to the candle, what do we get?” she asked, putting deed to word.

“More fire,” said Peter. “But what does this have to do with my bike?”

“Hand me some of that steel wool and you’ll see,” she replied. “What will happen when I put the steel wool into the flame?

“It will get hot and maybe glow,” said peter.

“Hold it,” Daniel interrupted. “Remember that she said you left your bike to burn. Maybe the steel will burn!”

“There’s only one way to find out,” Peter’s mother said. “Ready?”

What do you think will happen? Do the experiment!

 

 

 

 

 

 

 

Peter’s mother stretched out the steel wool so that a few, wispy strands stuck out and then put them into the candle’s flame. As the boys watched with astonishment, the steel wool caught fire and started to burn, dropping glowing embers of molten steel onto the concrete floor.

“That is so cool!” Daniel shouted. “But what’s going on?”

“What we’ve done is speed up the process that makes rust,” Peter’s mother replied. “When iron meets oxygen, they swap electrons; that binds the two together in a process that the chemist calls oxidation and the rest of us call rusting. The same thing happens when the carbon in the candle wick meets oxygen; the chemist still calls it oxidation but we call it fire.”

“So a rusting bridge is really on fire?” Peter asked. “That’s weird.”

“Weird but true,” his mother said. “And it’s not just bridges. Even diamonds are slowly oxidizing; Antoine Lavoisier even set a diamond on fire in 1772.There are ways of speeding up the reaction. One is by adding heat; most chemical reactions go faster when the temperature goes up.”

“Is that why the steel wool caught fire in the flame?” Daniel asked.

“That’s part of it. We also made the steel very thin which exposed more of it to the oxygen in the air and that helps, too. And another way to speed things up is by adding a catalyst, “seeing their puzzled looks she added “that’s a chemical that helps a chemical reaction happen but isn’t part of the reaction. For rust, one of the most common catalysts is salt.”

“How can salt help something burn?” Peter asked.

“The salt dissolves in water into sodium and chlorine ions. Those act sort of like little ferryboats, bringing more oxygen to the iron in the steel. That speeds up the reaction. So if you wash off the salt, like Daniel did…”

“Then the catalyst is washed away, Peter said. “But what does the oil do?”

“It keeps the oxygen in the air from getting to the iron, so the chain can’t rust. And that is why Daniel can ride his bike today while you are stuck cleaning yours,” she added.

“There’s just one way to fix that,” Daniel said. “Let’s get back to de burning this bike!”

And with that, the two boys bent to their task, happy with the knowledge that they wouldn’t have to do it again because they now knew how to keep their bikes from burning.

 

May 30 – It’s A Snap

One of the amazing things about science is that what you learn when you study one thing often applies to something else that you wouldn’t think was related at all. In today’s adventure, Daniel, Peter, and Mary discover that spaghetti, earthquakes, animals, and authors all have a secret connection.

 

When Peter’s mother walked into her kitchen, the last thing she expected to see was pieces of spaghetti lying all over the table with Mary and Peter laughing over them. But that’s exactly what she saw. Peter and Mary were sitting on opposite sides of the table, watching each others’ hands very closely as they took turns picking up pieces of spaghetti and snapping them.

“Hey,” Peter’s mother said. “What are you two doing?”

“We’re doing an experiment,” Peter explained. “I read somewhere that spaghetti always breaks into two pieces when you snap it and Mary didn’t believe me. So we decided to see if it was true.”

Looking at the pile of broken spaghetti, his mother shook his head.

“I know that you are supposed to replicate your results, but why so many times? ” she asked. “You should have been able to answer it with the first few pieces.”

“Well,” Peter said. “I can get the spaghetti to break into two pieces pretty consistently but Mary almost always gets three pieces except when she gets four. We’re trying to figure out why.”

“Well, it certainly looks as if you’ve done a pretty thorough job. But have you even decided what the variables are in your experiment?”

“Well, no, ” the two admitted sheepishly.

“So what you are really doing is making a mess,” his mother admonished. “If you don’t know what you’re doing, then you can hardly know if you are doing it right. Tell you what. If you’ll sweep all of this mess into a bowl so we can use it for dinner tonight -”

“Oh, boy! Spaghetti!” Mary interrupted.

“-then I’ll show you a real experiment with spaghetti. Deal?”

By way of agreeing, Peter and Mary quickly jumped up then gathered up the spaghetti pieces into a bowl. Once the table was clear, Peter’s mother put five pieces of whole spaghetti in front of each of them along with a penny.

“Here’s the experiment,” she explained. “What you’ll do is pick up each piece of spaghetti in turn, working from left to right. The other person will flip their coin. If they get heads, then you have to snap the spaghetti into two pieces of equal length by holding it in the middle; you then put the two pieces at the far right side. If the other person gets tails, then you put the piece of spaghetti at the far right and you don’t snap it. Got it?” At their nods, he continued. “You’ll each flip your coin forty times. So you know the variable – the coin flips. Here’s the question: How many pieces of spaghetti will you have at the end?”

“Well, we start with five pieces,” Peter said. “So each one will get eight flips. If they get broken half the time, then each piece should get broken four times giving us two pieces each time and we’ll have five times four times two or forty pieces.”

“I don’t think that’s how it will work,” Mary said. “Remember that this is random. So some of the pieces will get broken more than once and others won’t get broken at all. So it will probably be less than that; I think it will be closer to thirty pieces.”

“Good,” Peter’s mother said. “And notice that you both added an extra prediction. Peter seems to think that the pieces will all be about the same size but Mary, you think that they’ll be different sizes.”

“That’s right,” Peter said.

“Well, there’s only one way to find out,” Peter’s mother said. “Start flipping!”

What do you think will happen? Do the experiment!

 

 

 

 

 

 

For the next ten minutes, the kitchen was filled with the sound of flipping coins and breaking spaghetti. Soon, some of the strands looked less like spaghetti and more like toothpicks while other strands stayed long. At the end of all the flipping, they quickly counted up their pieces of spaghetti.

“Hey! I only got twenty-five pieces!” Peter exclaimed.

“Yes, and one of yours is still whole,” Mary added. “I have thirty pieces but none of mine are longer than a half.”

“So what gives?” Peter asked. “I kept track – we both got the same number of heads.”

“Ah, but did you get them in the same order?” Peter’s mother asked. “Because you kept cycling through the pieces in a strict order, getting heads or tails at a different time meant that you’d get a different length. But, if it makes you feel any better, if you had done more flips on more strands of spaghetti, then you would both have gotten almost identical results. Yours are actually pretty close, given how few times you flipped the coins.”

“How many would we have needed in order to get the same result?” Mary asked.

“An infinite number,” she replied. “But if you’d flipped your coins about 1000 times and used ten strands of spaghetti each, then you two would have been much, much closer.”

“But why didn’t we get forty pieces each?” Peter asked.

“It is just like Mary said – you forgot that you’d be flipping on individual pieces and not the whole strand each time; there’s a fun little math equation that describes what will happen. But what’s really cool about this is that you can do the math backwards and find missing things. Take asteroids for example,” she explained. “We know how many we have found and what their approximate sizes are. By applying that equation, we can predict how many we haven’t found.”

“Cool! Is that why they say that we know where 90% of the big ones are?” Mary asked.

“Yes. But the math doesn’t just apply to rocks in space; it also tells us what the distribution of rocks in an avalanche will look like, and how the number of earthquakes will change with size, and even the number of fish of a given size that are hiding in a lake. Alfred Lotka even used it to predict the number of scientific papers that would be written in any given year.”

“What? How did he do that?” Peter asked.

“He just looked at the number of papers that were written by an scientist who had already published a paper. Let’s say that in one year, there were 500 scientists who each published a paper and that the next year just 125 of them published another paper. Then he knew that in ten years there would only be five of them who wrote a new paper. If you then add up all of the people who were doing research and assumed that they stopped after ten years, you’d just add up the number of scientists publishing for the first time, the second time, and so forth, and discover that there would be 774 papers published that year,” Peter’s mother said. “The neat thing is that it isn’t just papers that you can do that way; it also tells you how emails would be written in a given year and how many blog posts or how many television shows would be filmed.”

“That is so cool!” Mary said. “I didn’t know that one equation could do so much.”

“Well, there is one thing that it can’t do,” Peter’s mother said. “It can’t clear the table so I can make spaghetti!”

With a quick grin, the two hungry young scientists turned to the table and started cleaning up their experiment.

 

 

About the scientist

In 1918, an influenza pandemic swept across the globe and killed one out of every twenty people alive at the time. It was the greatest health disaster since the Black Death and inspired many scientists to find new and better ways of predicting disease outbreaks. One of these was Alfred Lotka who was trained as both a biologist and a mathematician. He had been working on ways of predicting malaria outbreaks and soon discovered that his work was more widely applicable than he had expected.

He started looking at the number of papers published by scientists, At first, he was just curious about why so many scientists seemed to write fewer papers as they got older but he was surprised when he found that he could actually predict how many papers would be published using a simple formula. His result turned out to be a special case of a more general equation that governs everything from animal populations to gravel size to the number of sunspots.