They mine and countermine, until it isn't safe to predict who is immune and who isn't.
Countermine:—As before, but moored 29-1/4' below the surface.
It is not an easy matter to decide just where the countermine should be sunk or how far to go.
I know where the mine is to be sprung; and I will countermine!'
They mine and countermine expeditiously in the Channel Fleet.
He knew you, madam, and was resolved to countermine you in all your plots.
The springing of their countermine, he found, was no deliverance.
During the night the Italians exploded a countermine, which destroyed the Austrian gallery.
So Paul concealed his plans from Madame Astier, in entire ignorance that she was running a countermine in the same line as his.
Though he was well versed in the arts of diplomacy and could meet mine by countermine, he never resorted to trickery.