UselessFinds
A Bottle Of Liquid That Grows Spikes When You Point At It

the magnet is separate on purpose

Desk Toys

A Bottle Of Liquid That Grows Spikes When You Point At It

A sealed glass bottle of ferrofluid and a small magnet. Bring them together and the black liquid erupts into spikes.

Buy this nonsense$22.38$10.97(sponsored link, opens in a new tab)
  • ferrofluid
  • magnetic liquid
  • desk toy
  • science toy
  • stress relief
  • physics

What Is This Thing?

A small rectangular glass bottle holding black ferrofluid — a liquid with nanoscale iron particles suspended in it — and, packed separately, a stubby black magnet.

On its own the liquid sits at the bottom looking like ink. Bring the magnet to the outside of the glass and it climbs the wall toward it and erupts into a dense field of spikes, each one standing along a magnetic field line. Move the magnet and the spikes follow. Take it away and the whole structure collapses back into a puddle.

Why You Don't Need It

It is a bottle of dirty-looking liquid that does one trick. There is no second mode, no light, no sound, and the trick lasts about four seconds before you have to move the magnet again.

The spikes also never look quite as sharp as the product photographs, because those are shot with studio lighting against a black background and yours will be on a desk.

Why You'll Buy It Anyway

Because the shape is not decorative — it is the magnetic field, made visible. The spikes appear where the field lines are, which means you are looking directly at something that is otherwise entirely abstract, and the fact that a liquid can do this at all is genuinely strange.

It also has the rare property of being interesting to a physicist and to a six-year-old for exactly the same reason.

A Bottle Of Liquid That Grows Spikes When You Point At It — photograph 2
A Bottle Of Liquid That Grows Spikes When You Point At It — photograph 3

Who It's Actually For

Anyone with a desk and a short attention span. It is the object people pick up while thinking, and unlike most fidget toys it does not make a noise.

Also teachers. Field lines drawn on a whiteboard are an abstraction that students take on trust; this is the same diagram, in a bottle, and it takes ten seconds.

before you click buy

Keep the magnet away from cards, drives and anything else magnetic. It is small and it is strong, which is a combination that ends up in a laptop.

Ferrofluid stains permanently and the seal is the only thing between it and your desk. Check the reviews for leaks before buying the cheapest version of this you can find.

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