## Minecraft Lighthouse

A new world (revision 19) recently went live on the Nerd.nu survival server, so I decided to do something cool and new. In addition to starting work on a “bottomless tower” (building downward instead of up) just for the novelty of it, I threw together a working lighthouse on the tiny land formation in the harbor. It has a compact 5-clock powering glowstone lamps up top, with vertical torches transmitting the signal.

Unfortunately, the circuit tends to glitch and freeze up after awhile, and the light gets stuck on or off. Fixing it requires punching out and replacing a Redstone wire, then pushing the reset button nearby. I don’t know whether this is a limitation of the server, the game, or my repeater-based clock circuit.

If you log on to the server (s.nerd.nu), you’ll find it along the brown road.

Update: You can get a closer look at the (since improved) circuit powering the lamp here.

## Daring Fireball: The iPhone 5

Gruber reviews the iPhone 5.

## My Favorite Way to Illuminate a Minecraft Enchanting Room

Glowstone block goes under the enchanting table. Now it looks 75% more magical.

## Compact Minecraft Double-Door Mechanism

If you’re playing Minecraft on a server that encourages PvP, it’s kind of important to have some form of security mechanism. Otherwise you’ll be considered an easy target, and players will constantly try to kill you.

The most common deterrent is to simply use iron doors, with a lever on the inside to open and close them, instead of simple wooden doors. However, anyone who’s tried to set up double-doors that open at the flip of a single switch, knows just how irritating it is. You need to have a redstone circuit that applies power to both doors at once, and those circuits often take up too much room. Unless you planned your base to have an outer wall and an exterior wall, with a large gap between them, you might be stuck having exposed redstone paraphernalia.

Since I don’t like having exposed wiring, I figured out a method of making a compact double-door mechanism that won’t require you to butcher your nice building to make it work.

This is what it looks like from below.

I bet that got your attention. That ensures that both doors open and close at the pull of the lever, while using far less space than what you’d find in most YouTube tutorials. The mechanism fits into a single row of blocks.

Of course, there are two layers of blocks involved here. The row that contains the mechanism and door is technically that one block-thick wall I was talking about earlier, but there’s a big stone staircase on the outside of the tower that conveniently covers it up. So I lucked out and had a two block-thick wall in this case.

You can see how it works a little better in this shot. The two dirt blocks have a single piece of redstone wire on top, with two repeaters in the middle. The left one brings the current down from the switch, the repeaters carry it over to the next block, which carries it back up to the second door. The switch is next to the left door, so it opens it simply by being in proximity. (Ignore the blank space on the bottom row of stone, I accidentally mined it.)

In the view from above, you can see the little dots of redstone wire on the dirt blocks. The one on the right is close enough to power the right-side door, and the lever sends power directly to the left door, as well as downward to the repeaters.

It’s an elegant solution, if you don’t mind a tiny repeater lag before the second door is triggered, and simple enough once you have it figured out.

## Security experts: Apple did Mac OS X Gatekeeper right

Interestingly, there have been cases where the radiation output from a coal plant has tripped the very sensitive sensors in nuclear plants several miles away.

Also, there is an important difference between ionizing and non-ionizing radiation. The vast majority of non-ionizing radiation you would ever be exposed to is harmless.

TL;DR: Twitter is ditching the hashbangs and moving the heavy lifting back to the server side. They’ve already started on the single tweet pages, as you can see here. Definitely faster.

## The Harzewski Effect

Term first coined in 1985 by Peter Harzewski that states, “Any random piece of visual material (film or video) - and any random piece of music will eventually synchronize and appear to be intentionally linked.”

To illustrate the effect, here is an animated image of Christopher Eccleston from the 2005 season of Doctor Who. If you combine it with a completely unrelated music sample, you get this.

The Harzewski Effect seems to have vanished from Wikipedia—apparently some of the editors decided it was a “neologism” and removed the article—but you can still see it referenced on some websites, such as the one for this media production company.

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