Tin is obtained from a mineral called cassiterite which is mined in Brazil, Bolivia, China, Indonesia, Malaysia and Peru. The Cornish mines in Britain were almost wiped during the price collapse in 1985. Cassiterite is basically tin oxide and needs to be smelted before use.

The cassiterite is smelted into metal by reducing it with carbon in a big furnace called the reverbratory furnace in temperatures in excess of 1200 degrees Celsius. The reverbratory furnace is a special furnace that isolates the tin oxide being smelted from the fuel that is powering the furnace. The hot gases that result from the burning of the fuel are the ones that are acting on the tin oxide.

The challenge in smelting casserite is that it is usually mined with other minerals mixed in it. Therefore, it is necessary to refine the tin to make it commercially viable. Refining the tin in a furnace involves various procedures before pure tin can be produced. For example, iron is removed from the molten tin by passing steam through it. Tin that are very impure can be refined using electrolysis to reach a pure level.

One of the main properties of tin is that it mixes quite well with other metals forming alloys. This alloy forming quality and low meting point makes tin a valuable resource. Tin is non-toxic and does not corrode and there fore it makes the ideal finishing coat for steel cans used to store food and drinks. This is how the tin can is made.

Pewter is a popular tin alloy used by craftsmen to create artistic designs used in household decorations. The shiny surface of pewter lends a certain charm to decorations and the ease of shaping this tin alloy allows many an artist to express their creative freedom. The fact that pewter will not rust or corrode ensures a long life for works of art.

Bronze is also an alloy of tin composed of tin and copper. Bronze metal were used by the ancient Roman army to forge their protective body armor and spear tips. Higher grade tin bronzes are also used to make bells.

Another alloy of tin that is very important today is the solder. Solders are used in electronics to create connections between microchips and the printed circuit boards that they sit on.

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As an instructor of English (reading, writing, lit, creative writing, etc.) and as an online course developer, I have found many valuable teacher resources for linguistic, literary, and rhetorical disciplines. Specifically for education and none for teaching in general, and a great many more with lesson plans for reading. Many of the lesson plans for reading are laid out so well that they will include peer work suggestions, interactive games and quizzes and maps, and dynamic and thorough strategies for cross-referencing studies.

As an example I used THE TIME MACHINE one semester. After a few decent lesson plans for reading, I found an incredible sight that was an invaluable resource that told me everything I needed to know about the author and his motivation for his work this was a wonderful resource, doing great justice to the writer, the work, and to students who are offered pre-reading, reading, and post-reading tasks and activities (as well as writing ideas/prompts). Here it is: The Time Machine High School Teacher’s Resource Page(s) - Http://www.sff.net/people/ james.van.pelt/wells/ timemachine.htm .

Yet another great example is for Harper Lee’s classic. For lesson plans for reading TO KILL a MOCKINGBIRD, I started at EdHelper.com; and went on with the incredible chapter-by-chapter synopsis of vocabulary words with The Student Survival Guide which is located here at this URL: http://www.lausd.k12.ca.us/Belmont_HS/tkm/; and concluded by taking advantage of some outstanding lesson plans for reading found at SCORE, the site designed and run by Schools of California Online Resources for Educators.

For lesson plans for reading Achebe’s THINGS FALL APART, I was able to locate a fantastic pre-reading historical, anthropological, and cartological exercises at the following location http://www.sdcoe.k12.ca.us/score/things/thingstg.html. This resource is broken down in a five-part cyber guide is basically set up as an informative piece for weeks and weeks of pre-, during-, and post-reading work.

And for lesson plans for reading, pre-reading, interim reading, and post-reading tasks, experiments, peer-work, and quizzes and tests, I found such sites as those sponsored, designed, and maintained by educators at all levelsat Proteacher.net; Teachers.net; TeacherOz.com; Webenglishteacher.com; sheboyganfalls.k12.wi.us/ staff/dehogue/AP/teachers/main.htm; readwritethink.org; teachersfirst.com; Awesomelibrary.org; mrscassel.com; and Teachnet.com to be absolutely exquisite resources that were extremely helpful.

A great advantage of the Internet is the fact that there are so many outstanding lesson plans for reading, writing, and any other discipline. Usually designed, written, and submitted by fellow instructors, these materials lend themselves to professional development, and our excellent for stimulating thought and discussion inside the classroom, or virtual classroom if that’s the case is outstanding as an aid to learning of concepts, strategies, methodologies, and skills. Hopefully these resources that I’ve shared for you will not only help you find lesson plans for reading but also many other valuable resources

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As the Peloponnesian War (431-404 B.C.) loomed with the worsening of the cold war between Athens and Laced

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You can’t believe a few years have gone by since you graduated from High School and yet you still don’t have a clue what to do with your life. How can you decide what career path to choose? You definitely know that you are tired of low-paying dead end jobs with absolutely no future. So what is the answer?

Online career training.

Career training is a very good way to learn new skills in a short amount of time. There are lots of career training programs, which can help you gain technical and/or business knowledge. Students can attend college for years, but do not receive very specific knowledge in a particular field because they are busy discussing theory instead of what is happening in the real world. Career training utilizes step-by-step online training based on current trends in industry.

Online training has come of age and millions of people yearly join online courses worldwide. You just require a computer and an internet connection to study from the luxury of your home. You can access your course from anywhere in the world.

Career training courses are designed in such a way that there are full instructions about the subject usually via streaming video and audio. They help you to gain valuable knowledge on a subject and include many types of questionnaires and tests so that you learn the subject very well.

There are many benefits of career training. You are taught the required skills for doing a particular job and it is a very convenient way to study. If you are working or managing a business, you can study and take your tests anytime, anywhere. There is no need for you to commute or attend classes.

There are lots of online training courses and it is very easy to enroll. You simply register for the course and you will receive login information. Use this information to login to the website and from there you can access the course materials and begin your training. Some websites allow you to take mock tests to judge your skills and knowledge while others provide online career counseling.

Once you complete a course you can get a job because you have skills. Most employers want to hire people who have experience. Your career training course will give you the hands-on experience needed. Yes, career training helps facilitate getting a job because you get the requisite experience you won’t receive from a standard classroom education.

There are lots of career training courses available and by doing your research you can join a program that you really like and that will pay off.

Copyright 2006 Sherry Harris

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Every year around December, about 200 to 250 female polar bears give birth to twins or triplets in the park area. They are part of a population of about 1,200 polar bears in and around the park, some 600 miles north of Winnipeg in northern Manitoba. The females fast during the first months with their cubs, but as spring approaches, they grab their cubs and make a run out onto the ice. The females desperately need food by this time and much reach the Hudson Bay before the ice breaks up and the ringed seals, the favorite food of the Wapusk National Park polar bears, disappear. It will take a family of polar bears about two to three weeks to make it to the ice, during which time each female will probably lose one or more her cubs. It’s a tough journey.

Once the family reaches the ice, they’ll feast on seals. The mother will teach whatever number of cubs survive how to hunt for themselves. If the cubs get through their first months outdoors, they’ll spend the next two years by their mother’s side, migrating to and from the Arctic ice packs and learning to hunt the seals. Polar bears gorge themselves during the seven to eight months of the year when the ringed seal is available. During that time they can triple their body weight. Males may grow to 1,000 pounds or more during their feeding period while females may reach 600 pounds. They’ll need the extra weight to get them through the summer when the ice breaks up a=on the Hudson Bay and the polar bears move inland onto the summer tundra.

Polar bears are the world’s largest land-based predator. They have only one enemy, traditional Inuit natives who hunt the bear for their meat and fur. But now they have another enemy - human-caused global warming. Today, ice melts in the Hudson three weeks earlier in the spring than it did just 25 years ago.

The increasing sun and early ice melt means there is less time for the polar bears to fatten up for the summer months when they won’t have access to the seals. Polar bears amass most of their body fat during their spring feast of ringed seals. When the ice disappears earlier, they aren’t able to put on as much fat. That fat is critical for the males, but even more critical for the females who must fast an additional period while they nurse their cubs. Females lose an enormous amount of weight giving birth and caring for their cubs, but gain it back if they have enough time on the ice. One female weighed only 250 pounds after her pup’s birth, but ballooned to 880 the next year.

But scientists have noted a 10 percent drop in the number of cubs born in the last 20 years. Adult bears are also 10 percent thinner. At a lower body weight, females have a tougher time nursing, which is part of the reason there are fewer cubs. Female polar bears use snow dens to give birth to their cubs. But rising temperatures can affect these dens themselves. If the dens melt early, the cubs are exposed to the outside world too soon. The same is also true for the ringed seals, which are the prey of the polar bears. They use snow dens to shelter their young. Without the snow dens the health of both predator and prey are affected.

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