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Christmas Gift Guide

Pseudoscope

Spinthariscope

Spectroscope

Field's metal

Flame colouring chemicals

UV torch and ink

Gyroscope

Orrery

Zoetrope

Planet globes

Wimshurst machine

Sunspotter solar telescope

If you want to mess with your head, without putting illicit substances in your bloodstream (or while, we won't judge you), there are few things better than an optical illusion. A pseudoscope lets you view the world through the lens of Escher; or rather, in simpler terms, it swaps what you see with your left eye with what you see with your right eye, bringing the background forward, and pushing the foreground back. It will mess with your perception, man!

You can make one from a kit, or collect the parts and follow a tutorial to make one, yourself.

Caption by / Photo by Grand Illusions

Ever wanted to see an atom split? Using a spinthariscope, you can. Invented in 1903 by Sir William Crookes, they contain a tiny amount of radioactive material — in the case of this one from United Nuclear, that material is Thorium, which is naturally radioactive and is permanently sealed within the device.

As the Thorium decays, it expels exploding particles (they can't penetrate the casing, don't worry), which emit a tiny flash of light when they come into contact with a sheet of Zinc Sulfide, directly above the Thorium. You can peer through the lens that is affixed to the top, to see teeny tiny nuclear explosions in action. Cooooool.

You can read more about the history of the spinthariscope here.

Caption by / Photo by United Nuclear

Curiosity is using a spectroscope up on Mars to analyse the chemical elements it finds, but you can make a simple one using materials you have around the home. A spectroscope is an instrument that is used for examining light waves; more specifically, which parts of white light are absorbed by elements. Each element has its own spectral "fingerprint" — scientists study these fingerprints to determine the make-up of stones, gases and other elements.

The spectroscope project here uses a box and an old CD, but you can find proper pocket spectroscopes, such as the kind used by gemologists, online.

Caption by / Photo by Sci-Toys

Field's metal — or Gallium — is an element with a very low melting-point — 29.77 °C, to be a little more exact. That is below the average human body temperature, so you can melt it just by holding it in your hand. It doesn't occur in nature, but it can be found in trace amounts in bauxite and zinc, and is also a by-product from the production of aluminium and zinc.

We're not really sure what you can do with it, but it seems like a really cool thing just to have and play with — and we particularly like the trick of handing a guest a spoon cast made from Gallium to use in a hot drink.

Caption by / Photo by Gallium crystals image by foobar, CC BY-SA 3.0

This one might be a bit difficult to obtain, but it will make your campfire look real snazzy while you're grilling a sausage. Each of the five chemicals changes the colour of flames.

Before you grow all disconsolate over its difficulty, you can probably purchase separate chemicals, at least. Chemicals that will change the colour of your flames, as directed on About.com (which also gives directions on how to use the chemicals), are:

Pink Lithium Chloride
Red Strontium Chloride or Strontium Nitrate
Orange Calcium Chloride
Yellow Sodium Chloride (table salt) or Sodium Carbonate
Yellowish-green Borax
Green Copper Sulfate or Boric Acid
Blue Copper Chloride
Violet 3 parts Potassium Sulfate 1 part Potassium Nitrate (saltpetre)
Purple Potassium Chloride
White Magnesium Sulfate (Epsom salts)

You can also get packs of "flame dye" locally at fire performance specialty shops, but they only come in red and green.

Caption by / Photo by Home of Poi

This one might be suited more for those days when you need to get your super-spy on, but wouldn't it be awesome to arrange a romantic date where you give your partner UV clues to meet you somewhere, adding an astral telescope for a night of stargazing? You can have that one; that one's on us.

Caption by / Photo by Ali Express

Gyroscopes — which we mostly discuss in relation to the motion-detection capabilities of smartphones and other gadgets — are devices that measure orientation. After developments over around 90 years, the gyroscope, as we more or less know it today, was developed by mathematicians, and has remained pretty much unchanged since then for larger applications (smaller devices, such as the iPhone, use a Micro-Electro-Mechanical chip). They're also pretty fun to watch — seeming to defy gravity as they, to quote mathematician Lewis Carroll out of context, "gyre and gimble". Read about how they work on How Stuff Works.

Caption by / Photo by Gyroscope.com

Orreries are absolutely gorgeous things. Remember in The Dark Crystal, Aughra's observatory, where she had a working model of her solar system? That's what an orrery is. It shows the relative positions of the Sun, the planets and, in more complicated models, other bodies in the solar system (although, not to scale, for obvious reasons), on overlapping rotating arms of varying length. They mostly operate on clockwork — you wind them up and watch how the planets move across the sky in relation to each other.

They can be a little pricey, but are things of beauty and wonder, indeed. If you can't afford to buy one outright, though, you can always have a crack at this kit from Grand Illusions.

Caption by / Photo by Curious Minds

Remember the zoetrope from activity books when you were a kid? It's basically a way to make an animated image. The slits in the "crown" mean that when you spin the zoetrope, you can see inside, kind of like quickly walking past fence palings.

The lower strip is where you can draw your animation images in a series of incremental movements, like you would in a flip-book. When the zoetrope spins, it goes too fast for you to pick out individual images, creating a very simple animation.

Maybe it's not particularly mad-science-y, but it is mad fun.

Caption by / Photo by Zoetrope image by Andrew Dunn, CC BY-SA 2.0

Why would you want just a boring old Earth globe, when you can have a levitating Jupiter globe? Or Neptune? Or even the mighty Saturn? Heck, why not collect them all?

Caption by / Photo by Stellanova

If you're feeling a spark of something special right now, that's probably because of the Wimshurst machine in the picture above — a device that generates static electricity. You might be more familiar with the Van de Graaff generator from high school science — but the added bonus of this particular Wimshurst machine is that you can make it yourself, using easy-to-find components. So not only do you get the benefit of a really cool gizmo, you can satisfy the hobbyist in yourself with a DIY project. Win.

Caption by / Photo by Jake von Slatt

We've all heard about telescopes for viewing far-away stars, but what about one for getting up close and personal — and without burning your eyes? The Sunspotter is a folded-Keplerian telescope that lets you view a three-inch image of the sun on a white screen to view solar activity, such as storms and spots. It'll cost you a few pennies, but watching the Transit of Venus live? Priceless.

Caption by / Photo by Sunspotter
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