How to make boiler in Little Alchemy

To make boiler in Little Alchemy you have to combine this elements:

1. metal + steam

Boiler Step by Step

How do I combine the necessary elements to create boiler in Little Alchemy?
Here we show you the walkthrough, just follow the steps below:

1 fire + water = steam

2 earth + fire = lava

3 air + lava = stone

4 fire + stone = metal

5 metal + steam = boiler

Below you can see a video tutorial on how to make boiler in Little Alchemy: