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Now you can - well perhaps you won't actually be walking on the ceiling but as you gaze through this brilliant device - it will look as if you are. You can also make your own rainbows, bend light and make your home into a carnival house very much like a house of mirrors with the walls, doors and furniture warped and twisted. And the best thing of all - no batteries are required.
I'm not quite sure how long prisms have been around. One of my best childhood memories is of a very kind lending me on for spring break. I spent 2 weeks walking around everywhere holding one of over my eyes. The teacher had simply warned me - "For God's sake don't step into a road with it", and let me take it away to have fun. Of course now it is questionable if a child would even be allowed to play with this in class, it does have sharp corners, it is made of glass, and walking about looking through this is very strange experience, but that was in the glorious days before health and safety banned fun. If you got hurt then, your parents told you to be more careful - they didn't run to the solicitors.
I also know Isaac Newton had a prism, and if were still alive, he'd be a good bit older than I am. Glass was expensive then, and Newton could not afford to have a glass maker custom make him a 3 sided glass,so he used 3 pieces of window pane stuck together with sap, and filled with resulting triangle with water - I'm not quite sure what he used for a base. He used this to project a beautiful rainbow like spectrum of colours onto a white background, showing for the first time that light was made up of all of the colours. This was completely different from the prevailing scientific theory of the time, that colours were made of a mixture of dark and light. Ordinary white light was thought to be without any colour. Newton proved this was false by separating the light into the spectrum of colours, and then using a second prism to refract the light back into a single beam of white light. However, Newton did not invent the prism, they were around before, scientists just thought the glass added colour to the light.
Ever since borrowing my teachers prism, I wanted one. This was top of my Christmas list for many years, but sadly I never saw another prism in my childhood. They were considered more of a teaching item then a toy, and not something you would have picked up in local shop or catalogue. Even now, if you want one of these you will most likely have to order online. This means you won't get to try it out first, so it is important to get the right one. Many of these ship from China or Hong kong, so if you are in a hurry, be sure you find a UK seller and expect to pay a higher price.
I have read in several places that it does not matter if the prism is glass or plastic. I believed this and bought a plastic one first and was terribly dissapointed. It really is not anywhere near as good. This particular one is listed on amazon as Physics Teaching Precision Optical Glass Prism. It is sold by Suntek online. It came in a lovely red box with a paaded cut out shape to keep the prism safe and gold writing - in Chinese. I haven't a clue what it said, but the children did take some interest in viewing the writing as well, so a brief lesson in other cultures and styles of writing. There are no instructions, but you won't really need any. This is simple enough to use, and I'll be including some quick instructions below. I don't really think brand name will matter on this, I believe any 6" glass prism will have the same effect. but I have just ordered a 6" prism from ebay at £5.12 so if there is any difference I will update. This was £7.99 on Amazon but has just gone up to £9.99. I've found what appears to be the same prism from a UK seller at £9.19 on Amazon listed as BestDealUK Optical Glass Triple Triangular Prism Physics , but prices start at only £5.12 for this size on ebay.
Size does matter here as well, and I really can't recommend strongly enough, if you decide to buy one, buy a proper optical glass at least 4" in length. I have two prisms from this company, one measuring 4" and one measuring 6". I really do feel that 4" is the minimum size worth considering. There are several 2" models available as well, and you can use these smaller ones to refract light and create a rainbow, but it is more difficult to get it positioned just right ( my plastic one is tiny as well). A 2" prism will bend a laser torches beam just as well as a larger prism. But you can not hold a 2" prism over both eyes and it isn't nearly as much fun with just one eye. Also we have not tried this for trick photography yet, I'm waiting for a more consistently sunny day, but I understand you can all sorts of fun with this as well, but the larger prism is required. The children do prefer the 6" prism, but there really is not a lot of difference in use.
We have used this to show the children the colours of light. The very best effect requires sunlight - without clouds. This can be difficult in Northern Ireland. But when you do get a good bright patch of sunlight, you run outside as fast you can before it is gone, hold the prism and project rainbows on to walls, doors or anything else. If the sunlight is weak you might want to tape a white paper to the wall to display the rainbow, but if you have decent sunlight you can project it onto anything, even people. This can be done to some extent with a strong torch, but it isn't nearly as good.
We have also used this to split up the light from a lantern and to even an ordinary energy saving light bulb. looking directly through the prism. Don't give up if you don;'t see anything at first, it is just a matter of tilting the prism back and forth until you get the right position. We've used this to look at TV's, the computer, the aquarium and anything else with a light source seeing if we can pick up rainbows.
Looking through the prism directly will curve and distort images too. You can stretch and shorten things, curve the shapes or even make everything upside down. We have fun looking at the fish, at each other, at the walls and ceilings. We do use these walking about as well. This requires two people. One holds the prism horizontally and one watches and says stop if the walker if they are going to walk into something. The extra person or people also have fun laughing at the person with the prism staggering about like a drunken sailor. If you tilt the prism right, it really does look like you are walking on the ceiling. Another angle will give you the effect of the earth curving away beneath your feet. It is very difficult to walk a straight line though you end up trying to compensate for the fact that everything looks so strange, and it gives you a dizzy feeling after awhile.
We've also used this to make a pretend burglar alarm in the teen titans house. By shining a laser torch through this and then bouncing the beam off of mirrors you can have all sorts of fun.
Unfortunately, I could not completely replicate Newtons experiment. This requires two prisms, and my plastic one simply is not good enough. I have ordered a 2nd prism so we can split the light and then refract the colours back into one, recreating the famous experiment.
My sons absolutely love this, and another reason for buying a second prism is to allow them both to play at the same time. Like many parents, I have felt at times pressured to by the latest electronic gadget which is meant to help a child's education, but having a limited budget, many of these have been out of my price range. But I have found when I have managed to buy many of these things, they simply do not provide as much entertainment or education as the older more simple items. An electronic game can only be used one way, and by it's nature, it directs game play. The child can not invent their own ways to play. I love this toy because it encourages children to think, and be creative, to find new ways to enjoy it. I do not really use this for teaching, but just as a wonderful play thing, but I believe the children learn much more just playing with this than with formal lessons. I think they remember something more when they discover and experience it themselves. I do show them the odd trick with this, but I believe they learn so much more by discovering the properties of this on their own than they would with proper lessons. However, in a classroom situation, I do think this could be a brilliant teaching tool as well, with a teacher demonstrating the properties of light.
This is sold on Amazon under toys and games, but most sellers refer to it as a physics teaching prism., and the only glass prism to have an age range is recommended for ages 10 +. The corners of this are flattened so as not to reach a sharp point, but I do still feel a child could hurt themself if the fell and hit an eye and the prism was held vertically.and it is glass. I'm sure a child could break this if they dropped it on something hard enough, like the hearth, but it has survived being dropped on the floor from a child's height. We do use this as a toy, but it is a special toy, like our chemistry sets, that is used under adult supervision, rather than thrown in a toy box.
If you can afford to buy two of these, I would, simply so you can fully recreate Newton's experiments, just google "Newton and the Color Spectrum" and you should find plenty of information. However, you can still have plenty of fun with one. A few extras to make this more fun include: small mirrors, a laser pointer, and a book about the properties of light. I'm using Richard Hammond's Can You Feel the Force, which has a small section on light and Scholastic's Discovery Box light, but I'm thinking of ordering DK's Eyewitness Light as well. If anyone can recommend a better book on the properties of light for a young child please message me.