A little history
The idea is old as gunpowder; however, there were many problems to achieve an effective and reliable naval mine. The naval mine as explosive device was similar to Granada or landmine on general considerations, with a small but important difference must operate continuously in one of the worst environments. The sea water is extremely corrosive to metal, because all minerals hauling; temperature changes do likewise, as the constant movement.
The first naval mines were rough, huge and doubly dangerous instruments. The land minefields are marked by engineers on maps, so that friendly troops know to avoid them. However, the most precarious naval mines were little more than masses of explosives with fuses contact. Wandering adrift, could impact any vessel, whether friend or foe, military or civilian.
As in other cases, there is written evidence that the Chinese were the first to think of the creation of naval mines practices, to the sixteenth century. These were simple boxes sealed with weather systems, which were lit after wandering in the stream. Apparently other systems included a more effective system: from the coast, a man ambushed tossed the box, which contained a spark wheel system like some muskets. Pulling the rope, the sparks burned gunpowder.
These early mines, however, must not have caused much damage, although a great psychological effect. In the West its use was not much later. The first prototype Rabbards registered belongs to Ralph, who presented his design to Queen Elizabeth I of England in 1574. At that time also a Dutch inventor Cornelius Drebbel name did the same with King Charles I of England, and there is evidence that argues that such weapons were tested in the siege of La Rochelle in 1627, in British hands.
However, it would be the other side of the Atlantic where the first naval mines practices would be used. Designed by David Bushnell, were simply sealed boxes filled with gunpowder, floating towards the enemy with the flow and ignited if bumped against something. And he used precisely in the American War of Independence, against the British.
At that time the British were not with him also because the Russians used their naval mines against them in the Crimea. In 1812 a Russian engineer Pavel Shilling name had developed a device that detonated by electric circuit, and in 1854 similar models damaged three British ships.
im sorry,but i think the naval mines existe from the 15 century..