Interpret act 2 scene 5 line 10 of shakespeare romeo & juliet. and in their triumph die like fire & powder?

in those days , the only pistols were flintlocks and it took a spark of fire to set off the powder to lauch the projectile from the barrell . What this says is that if Rome and Juliet both dying they will be at peace together with no arguments and that like that once the gun is fired the fire and powder for that round die too as did the two lovers .