Life forms of an organic nature had penetrated the ship by an unknown means.

She somehow learned, by means unknown to us, that an expedition was planned to the solar focus.

A hitherto unknown means was introduced in the electric art.

Word comes that the town of Bandon has been destroyed by unknown means.

He answered that mapping the unknown means making it available to our perception.

"By what unknown scientific means do you appear in our city?"

He later appeared alive with his youth apparently restored by unknown means.

Investigative means from unknown to known, marching toward the darkness.

By some unknown means, a servant appeared to open it for them.

By some unknown means they were able to approach us undetected until it was almost too late.