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I'm currently looking into the how redstone works in Minecraft and I stumbled across this behaviour and I can't explain why this works.

Obsidian Block: O
Redstone Wire: |, +, -
Glowstone Lamp: L


Right so if I power the redstone wire, all three Lamps light up although there is no real connection to them. This however won't light the Lamp:


I read through the Minecraft wiki but there was nothing explaining this. How does this work?

marked as duplicate by Ronan, MBraedley, user28379, Schism, Frank Jun 28 '13 at 1:49

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  • 6
    I summon SCREENSHOTS – Ender Jun 27 '13 at 20:49
  • Since you are new to Arqade, let me explain why Ender has requested Screen Shots. It's because there are a lot of possible reasons why it's failing, and while your description is pretty thorough, it isn't thorough enough. Screen shots are typically a much better means of communicating these kinds of problems. – John Jun 27 '13 at 21:30

When a repeater, comparitor or redstone dust is pointing directly into a block (not over or around it), that block becomes what we call "powered", meaning that any of the redstone sensitive blocks (doors, pistons, lamps...) adjacent to it will activate. The direction of the line matters!

  • Note that single slabs do not conduct this charge, meaning that a switch sitting on top of a single slab in the top half of a block will not transfer current to the other 5 sides of the slab. – Coronus Jun 27 '13 at 21:41

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