He first appeared on the Artillery establishment in 1618. We know little of his early history, but in 1686 when the Bombardier came into being there appeared one Chief Petardier and four Petardiers with the same pay and status as their Bombardier cousins.
His specialty was the 'petard', a type of mine said to have been invented by the Huguenots around 1589. It was a bell-shaped gunpowder-filled container of brass or iron fixed to a wooden base. By exploding the device against the door of a fort or other work the Petardier hoped to demolish it. The Firemaster was expected to train Petardiers in its use.
To quote the old drill book "... a strong hooke is to be scrued into the substance you intend to ruine; and upon the hooke hangs the wringle (ring) of the Petard, and likewise to be shored up with a strong forked Rest to stay the Reverse of it..." There follows directions for filling and fuzing the Petard plus a final warning "... the Petardire must be careful to avoyd the danger of her Reverse by retyring in side line from it." We can imagine him invoking St Barbara as he lit the fuze!
Now action and reaction being what they are, in the event of the door being too strong, the petard can easily be pictured becoming a projectile to the extreme discomfort of the Petardier who had not kept strictly to the drill and 'retyred' according to instructions. Evidence that petards did sometimes backfire comes down to us in the present-day expression 'hoist with his own petard'.
As use of the petard diminished the duties of the Petardier and Bombardier became interchangeable, so eventually one had to go. The Bombardiers survived, while the Petardiers were wasted out. After 1728 they ceased to be held on establishment.