1 Geology. W: Today, I’ll begin with the basics about minerals. It’s important that you supplement this information by reading chapter 3 in your textbook because I’m sticking only to the bare bones here. All right...it’s essential to remember that both chemical composition and crystal structure together define a mineral. Some students find that surprising. They think that crystals are pure --- just one element. That may be true for some crystals, but not all. Minerals range in composition from pure elements and simple salts to very complex silicates with thousands of known forms. So to define a mineral, we have to figure its composition. What all is in it? Now, here is a useful tip that may save you a point or two on the next exam. Organic compounds are usually excluded from the category mineral. Got that? If it’s organic, don’t classify it as a mineral. In fact, there are five main criteria for calling something a mineral. Let’s go through those criteria. First of all, it must be in a solid state, not liquid, gas, or plasma. Minerals are solid. Second, it must be naturally occurring. In other words, it can’t be man-made. Third, it has to be inorganic. Like I said, if it’s organic, it’s not a mineral. So third --- oh, sorry --- we’re on number four now. Fourth, for something to be a mineral, it needs to have a fixed composition, which means the chemical composition is the same everywhere it is found and every time it is found. Mineral X found in my backyard is going to have the same composition as Mineral X found in Australia. Finally, our fifth criterion is that a mineral must be either an element or a compound; so it cannot be a mixture of a chemical compound and an element. Don’t worry if that last one seems a bit vague at the moment. We’ll talk a lot more about that over the next couple of classes. Sometimes we get certain cases that satisfy all but one criterion. That’s close, but not a mineral. These things are usually classified as mineraloids. Pearls would be a good example. Pearls are solid. They occur naturally. They have a fixed composition, and they’re a compound. The only criterion they don’t meet is the “inorganic test.” Pearls are actually a mixture of organic and inorganic substances. So, because they have that extra organic stuff mixed in, we can’t classify them as minerals. Pearls should be called mineraloids. Now, here’s another interesting case. Two or more minerals may have the same chemical composition, but differ in crystal structure. These are known as polymorphs. A good example of a polymorph pair is pyrite and marcasite, which are both iron sulfide. Let’s create a simple analogy to help you grasp that concept in case you’re confused. Let’s say Michelangelo has one large piece of marble. He splits it in two. One piece, he carves into the shape of a horse, and the other piece into the shape of a woman. They are exactly the same in chemical composition, but nobody would really claim they’re the same after he’s finished. Think of pyrite and marcasite as two of nature’s sculptures, both made of iron sulfide! All right, let’s see if you’ve been listening (laughs). Here’s my question. How about frozen H2O...or ice in layman’s terms? Is it a mineral? Anybody? Yes, Sam? M: Well, I’m not positive about this, but...in liquid state, it’s just a chemical compound, right? But as ice it becomes a mineral. W: We’ve got the five criteria for minerals, right? Tell me about each one in terms of ice and we can check. M: OK. Ice is a solid with crystalline structure, and it’s not a humanmade substance. Ice isn’t alive and never has been; it’s...how did you put it?...exactly the same everywhere you find it and every time you find it, or whatever; it’s a pure compound although it might have other elements suspended in it. Did I cover everything? W: Well done, Sam. I’m glad somebody was listening (laughs). You’re absolutely right. Ice is a mineral. M: Kind of strange though. Before this class, I never would have thought of ice as a mineral. W: I agree that it’s odd to think of it as a mineral. That’s because most of the minerals around us seem like metals or rocks. Most people forget that minerals come in many states of matter and forms. That’s why we have those five criteria for determining whether or not a substance is a mineral. Also, we need to keep in mind that both chemical composition and crystal structure together define a mineral. OK, so now we can identify minerals. But what can we do with them?
2 Campus Life.
W: Excuse me, Dr. Anderson? M: You must be Maria, come in. What seems to be the problem? W: Well, I’ve decided to change my major. I was majoring in chemistry, but now I’ve decided to major in psychology. M: That’s terrific. What area are you interested in? W: Well, that’s the problem. You see, because I was majoring in chemistry, I didn’t take any psychology classes in my second year. M: You’re in your third year now, I presume. W: That’s right, and I’d like to take developmental psychology. M: But it’s a third-year course and you don’t have the prerequisites. W: Exactly. M: So, just take some second-year courses this year, and next year you can take developmental. Unless you want to specialize in developmental... W: That’s just it. I want to go into child psychology. M: Well, I’m sure you know that it’s a little late in the game. Tell me, why the sudden change in plans? W: Well, over the summer, I did some volunteer work at the women’s shelter and spent a lot of time with the kids there. After working with children from violent homes, I really think I can make a difference in their lives. M: A noble endeavor. Tell me, have you thought about your thesis topic yet? W: No, not yet. I just made this decision a week ago, and I’ve only taken introductory psych. M: I understand. That’s why I think you shouldn’t be too hasty in making this decision. W: Why’s that? M: Well, like you said, you’ve only taken introductory psych. You may discover that you don’t like developmental. To be honest, it sounds to me like you might be more interested in social work. W: I suppose that’s another option. M: I’m not trying to discourage you. I’m just saying you should explore all of your options. W: But this is my third year. I have to decide now. M: OK. What I would suggest is this: first semester, you take a variety of psych courses. Get exposed to everything that the field has to offer. W: That’s a good idea. M: Now, I want you to know that we do set down prerequisites for a reason. W: Oh, I understand that, and I’ll work extra hard to catch up. M: I’m sure you will. Now, normally students take statistics in the first semester and research methods the next, but I want you to take both during the next semester. I’d like you to consider holding off on developmental until the semester after that, once you’ve got the methodologies down. W: OK, I’ll think about it, but I really would like to get started right away. M: Well, it is nice to see such an enthusiastic student. Take this permission slip when you go to the office to register. W: Oh, I really appreciate this, Dr. Anderson.
The pull movement follows a semicircle with the elbow higher than the hand and the hand pointing towards the center of the body and downward. The semicircle ends in front of the chest at the beginning of the ribcage. That constitutes the pull. Any questions about that? Sure, go ahead. M: I get it, basically, but I have a problem. My arms get tired really fast. W: And I’ll tell you why, Greg. I was watching you this morning, and it’s because your palms are too close together at the start of the pull. M: Oh, I see, but I thought a wide entry was a bad thing. W: Oh, it certainly is! The arms enter the water at shoulder width with the thumbs first. A wider entry loses movement in the next pull phase, and a smaller entry, where the hands touch, wastes energy. You need to find a happy medium. Got it? M: Yes, thanks. W: Next, the push. The swimmer pushes the palm backward through the water. The palm is underneath the body at the beginning of the push and at the side of the body at the end. The movement speeds up throughout the pull-push phase. Many swimmers make the mistake of thinking of the beginning of the pull as the focus. This leads them to neglect the push. In fact, that push should be fast and strong if you’re going to make a good recovery. It’s the only way to be truly efficient, looking at the arm movement as a whole, repeated process. Yes? Another question? M: Is it the same as you said with freestyle? You said we should keep applying pressure until our hand leaves the water in freestyle. W: It’s not exactly the same. For the butterfly, you need to make sure you actually increase the speed throughout the pull-push phase. In freestyle, it’s a uniform speed. We’re running out of time here, so if anybody else has questions, I’ll deal with them by the pool when I see you, but we need to talk about one point regarding recovery. As I said a few minutes ago, the speed at the end of the push is used to help with the recovery. Try not to use too much muscle during the recovery. The recovery swings the arms sideways across the water surface to the front, with the elbows slightly higher than the hands and shoulders. The arms have to be swung forward fast in order not to enter the water too early. If your arms enter the water too early, you lose a lot of momentum, forcing yourself to work a lot harder. A good rule of thumb is this: fly, don’t jump. Get used to going in and out using a fluid motion. Don’t jump in and out because that slows you down too much and tires you too quickly. Try to just skim the water. When you get used to it, it’ll feel like you’re just flying on top of the water. Pull, push, recovery, repeat. OK, that’s all for now.
W: I would like to discuss some of the historical events that led to the signing of the Magna Carta. The Magna Carta is the most famous document of British constitutional history and is widely considered to be the first step in what was a long process leading to the establishment of a constitutional monarchy. The Magna Carta required the king to give up a number of rights. As a result, the king had to follow certain legal procedures and to accept that the will of the king was not absolute. Let’s take a look at the background to all this. By the end of the 12th century, that is the late 1100s, the English king had become the most powerful monarch ever seen in Europe. At that time, the king of England even controlled part of northern France, Normandy. All of England’s possessions were controlled by barons, and the king ruled over the barons. However, when King John came to the throne in the early 13th century, he made a series of mistakes that led the barons of England to impose limitations on the king’s power. The Magna Carta was the result of disagreements between King John and his barons over the rights of the king. We can identify three principal failures of King John. First, King John was not respected. This was due to the way he took power. There had been two candidates to take the place of the previous king, Richard the Lionheart, who died in 1199. One was John, and the other was his nephew, Arthur of Brittany. John captured Arthur and imprisoned him. Although there was no proof, it was believed that John murdered Arthur. This, of course, led people to have a very low opinion of John as someone who would kill members of his own family to be king. His second failure occurred when he became involved in a dispute with the Church of England. John disagreed with the Church over who should be the next archbishop of Canterbury. The fight continued over several years, and in 1209, John was excommunicated. This meant he was no longer allowed to attend church services or be involved in the Church in any way. He finally had to give in to the Church in 1213. His third failure was in 1214. Philip Augustus, the King of France, took hold of most of the land in France owned by the English. The English barons demanded that John retake the land. John did make an attempt, but failed. In the process, the English lost a large amount of land, and as a result, King John was given the nickname John “Lackland.” By 1215, the barons were fed up and stormed London. They forced John to agree to a document known as the “Articles of the Barons,” and in return, the barons renewed their vows to be loyal to him. A formal document was created to record this agreement on July 15, 1215. This formal document was the original Magna Carta. The Magna Carta was composed of 63 different articles. Most of these were specific to society of the 13th century and thus irrelevant in contemporary times, but I would like to take a look at one of those articles, a very important article of the Magna Carta: Article 61. Article 61 was the most significant clause for King John. It was known as the “security article” and was the longest portion of the entire document. Article 61 established a committee of 25 barons who could at any time meet, and, if they felt it was necessary, had the power to overrule the king. This could be done through force by seizing his castles and possessions if needed. In addition, the King had to take an oath of loyalty to the committee of barons. However, King John had no intention of honoring the Magna Carta, as he had been forced to sign it, and Article 61 basically took away his powers. In other words, it made him King in name only. John renounced the Magna Carta as soon as the barons left London, which threw the whole country into a civil war, known as the First Barons’ War. John died in the middle of this war. His nine-year-old son was crowned King Henry III in late October 1216, and the war then ended. On November 12, 1216, the Magna Carta was reissued with Article 61 omitted.