Tuesday, December 14, 2010

The Colors That Make Up the World

The three primary colors are red, yellow and blue. However, the primary colors of light are different. They are green, red and blue. To make yellow, one mixes red and green lights. But to make white, ones mixes red, green and blue. Blue and green mix to make cyan, while red and blue light creates magenta. Who knew? The reason for this is because when two colors of light shine close enough to overlap, the eyes interpret the mixture as one color. An instrument called a spectroscope disperses these by bending through different angles. If you look at yellow through a spectrascope, you will see green and red. (How do people ever conceive these ideas?)

All visible things give off light. They give it off in two different ways. Some objects, like the sun, make their own light. Other objects, like the moon, reflect it. Things that don't give off light are colored by something called color subtraction. When a light falls on them, they absorb some of the color and reflect others. That is why a leaf looks green. It absorbs almost all the colors in the sunlight except for green. The reason blue paint looks blue is because it absorbs all the colors except blue. Black substances are ones that absorb all three. Yellow comes from substances that absorb blue light.

Friday, December 10, 2010


The University of Cambridge was closed. The plague had seen to that. It would open when the plague was over. However, plague couldn't stop Isaac Newton from studying. He was at his family's home in England while the university was closed, and, while there, made his three major scientific discoveries. The one I am going to talk about today was his discovery concerning light. One day, he darkened his room and made a tiny hole in the shades. This produced a stretched version of the sun. He decided to experiment by throwing light on a screen using a prism. It produced a top blue edge and a lower red edge. Then he decided to try sending the light down a tube before it reached the prism. The result was amazing. Instead of mainly white light, he saw a band of many colors. All the colors of the rainbow, in fact. He conducted other experiments and decided that light is many colors, not just one. (One of the experiments he conducted involved sticking things in his eyes. He almost lost his eyesight. Don't repeat his experiment. Being a genius does not guarantee that you will make wise decisions. It also does not guarantee that you will escape unscathed, although many famous scientists do seem to.)

There are two types of rainbows, primary and secondary. In a primary rainbow, light is reflected once as it travels through a raindrop.The colors are dispersed as they enter and leave the drop. It is likely that the colors depend on the position of the drop in the sky. Red light is seen from raindrops at an angle of 42 degrees to the line of the horizon, while blue light is seen from those at 40 degrees. All other colors are seen from drops between those. A secondary rainbow will form outside a primary one. The light is reflected twice by each raindrop, and the order of the colors is reversed. Red light is seen from raindrops that are at an angle of 50 degrees to the horizon, and blue light from those at 54 degrees.

Well, that's all for now. Just remember not to repeat Isaac Newton's experiment!

Tuesday, December 7, 2010

Tennis Balls and Cannon Balls

Henry V was a king of England during the Hundred Years War. The war was interrupted by plague, but unfortunately not ended. It was between France and England over a piece of land that the English said belonged them. The French, however, didn't agree, so a war started. King Henry V was the English king who came closest to winning. He decided to find a way to get the land without any more fighting, so he told the French king that it belonged to England by right of inheritance. His great-great-grandmother had been a French princess named Isabella, so he should've inheirited the land. He also demanded the French princess for his wife. The French king, Charles VI, knew he couldn't give the land to Henry, or his daughter, either. If he gave Henry the land, he would be admitting that land belonging to a French princess should go to the princess's children. And if he gave her his daughter, Henry could claim Katherine's children should inheirit all her lands, even if her children were English. Then Henry could claim his wife had a right to all of France!

King Charles sent King Henry a letter, saying the claims were false. The Dauphin, or prince, sent Henry several tennis balls and a message telling him he was acting like a child and to play tennis.
Needless to say, King Henry wasn't thrilled. The famous playwrite, William Shakespeare, wrote a play about this story, entitled Henry V. Here is Shakespeare's version of what the king said. The king probably didn't say quite what Shakespeare said he did, but they call that artistic license (or something like that. You know he wrote Macbeth in a week?)

We are glad the Dauphin is so pleasant with us....
When we have match'd our rackets to these balls
We will in France, by God's grace, play a set
Shall strike his father's crown into the hazard....
And tell the pleasant prince this mock of his
Hath turn'd his balls to gunstones....
....And tell the Dauphin
His jest will savour but of shallow wit
When thousands more weep than did laugh at it.
(Henry V, Act I, scene ii)
For those of you who think that was hard to read and doesn't sound at all like people (human ones, anyway) talking, I'm with you, but they always wrote plays more like poetry than real life talking in his day. If you didn't understand it at all, it basically says that Henry will turn the tennis balls to cannon balls and he's saying he's going to attack France.
Well, attack France King Henry did. And nothing went right. To cut a long story short, he was loosing and France wasn't cutting him any slack. They wouldn't let him retreat and met them at a place called Agincourt. Shakespeare imagined a fabulous speech for him to give in the play. The real one probably wasn't quite like this one.

This day is called the feast of Crispin.
He that outlives this day and comes safe home
Will stand a tiptoe when this day is named
And rouse him at the name of Crispin.
He that shall see this day and live t' old age
Will yearly on the vigil feast his neighbors,
And say "Tomorrow is Saint Crispin."
Then he will strip his sleeve and show his scars
And say "These wounds I had on Crispin's day."
Old men forget; yet all shall be forgot,
But he'll remember, with advantages,
What feats he did that day. Then shall our names
Familiar in his mouth as household words-
Harry the King, Bedford and Exter,
Warwick and Talbot, Salisbury and Gloucester-
Be in their flowing cups freshly remembered.
This story shall the good man teach his son,
And Crispin Crispain shall ne'er go by
From this day to the ending of the world
But we shall in it be remembered:
We few, we happy few, we band of brothers.
For he today that sheds his blood with me
Shall be my brother. Be he ne'er so vile,
This day shall gentle his condition .
And gentlemen in England now abed
Shall think themselves accursed they were not here,
And hold their manhoods cheap whiles any speaks
That fought with us upon Saint Crispin's day.
(Henry V, scene iii)

If you think that's hard to read, King Henry is telling his men that they are lucky to be fighting. Like I said, this isn't really what King Henry said. It's just what Shakespeare decided to write.

King Henry won the battle of Agincourt. He had far fewer men than the French, but he won anyway. Then King Henry took over a large piece of France, and the French king agreed to let Henry marry his daughter. He also said that when he died, King Henry could be the King of France. Unfortunately, he died two months before Charles VI died.