Abstract: Amusement devices including a water cannon are described, that include a reservoir member and a channel member disposed therein. A water cannon may also include a partition, or plunger member that partitions the interior of the reservoir and slides along the channel member. A water cannon includes an inlet to fill the reservoir with fluid. When full, a gas inlet, connected to a control mechanism and controlled by an operator releases a burst of gas such as air into the reservoir, thus driving the plunger member down the channel member through the interior of the reservoir and forcing a spurt or projectile of water out of the channel. A musical water fountain system may include a water cannon. The musical water fountain system may include a sound system for playing music, a water cannon system for producing projectiles of water and a lighting system for producing visual effects.