First, Second, Third, and Fourth NosLabs

Background

The first few versions of NosLabs didn't even have the mantra of "NosLabs" yet. They were simply referred to as "Wyatt's Lab," and were only one room.

The first NosLabs was on the fifth floor of the Flying Clown House HQ. It was an extremely bare-bones and tiny room, consisting of a redstone torch, a lever, a cauldron, an enchantment table, a furnace, and a crafting table. It was, to put it mildly, not fit for purpose.

Moving Up

At some point soon thereafter, Sean realized the first NosLabs was better suited as an office space than a science lab, and moved the second NosLabs up to the ninth floor.

It was a much longer room, but it had a much more limited feature set. It was encased in bedrock on the sides to protect the outside world from any explosions, it had a wall of uranium for nuclear test purposes, and featured a lockable door and required hazmat gear for anyone to enter the lab.

Still, even after this expansion, the lab was still constrained by the nature of the HQ, and the decision was made to move the lab away from the headquarters entirely.

Second NosLabs

Moving Out

The third NosLabs would be its own, separate building, located a distance away from the headquarters itself. Of the original incarnations, this lab had the most in it. It had a row of every vanilla ore that was implemented in Minecraft 1.5, a bookshelf, a dropper with each food that was available then, a chest with enchanted tools of every variety, as well as a chest with all the music discs and a jukebox. The third NosLabs also had a sink and a table with a ComputerCraft PC on it.

Third NosLabs

Fourth NosLabs

The fourth NosLabs would be located even further out as a slightly larger, but still single-room, building. It hosted a creeper observation room, but the rest of the facility was empty. There are no surviving images or world saves of the fourth lab, but it looked very similar to the third.