His face was set and rigid, his gestures and movements were guarded and slow.

He was keeping a tight hand on himself.

A very tight hand.

He had a vivid illusion--as vivid as reality almost--of being in charge of a slippery prisoner.

He sat opposite Almayer during that dinner--which was their last meal together--with a perfectly calm face and within him a growing terror of escape from his own self.
Now and then he would grasp the edge of the table and set his teeth hard in a sudden wave of acute despair, like one who, falling down a smooth and rapid declivity that ends in a precipice, digs his finger nails into the yielding surface and feels himself slipping helplessly to inevitable destruction.
Then, abruptly, came a relaxation of his muscles, the giving way of his will.