Minecraft wiki entry for TNT_cannons, associated text: Anvil "Baseball" cannon 1280M3ANVIL Cheaper Cannon that uses Eight Charge Pieces of TNT to launch 1 to 2 anvils up to 75 blocks on Ground Level and Further at a Higher Elevation Is Built by simply Wiring up Eight Dispensers to a Single Lever without a Delay and a Water Stream moving towards the two Anvils that are Hand loaded over an Upward Water Column that, If done Right, will cause the Anvils to Jump up and Down, the Cannon casing should contain a Slab preventing the TNT from Reaching the Water Column and a Basic Surrounding case. To fire Pull the Lever once when Both anvils are Staying low on the Water Column, By the time the TNT fires the one anvil will be leaping High, and if it is at the Apex of it's Leap, Will be Launched High into the Atmosphere and out of Sight. The Cannon gets the Baseball name due to the Similarities between it and Trying to hit a Ball floating on a Jet of Air with a bat. Currently Working on Adapting it to Launch TNT.