And when those mail sacks come flying out - sakes alive!

At dawn, a waiting plane would take the mail sacks and fly on.

I haven't let the cougar out of the mail sack, have I?

The permit and an extremely thin mail sack came to the ship by the same messenger.

Others were rushing about, some with mail sacks sealed to go.

A number of mail sacks containing these complaints were somehow lost.

Kidd was on the floor, stretched out along a row of mail sacks.

Nothing moved, except at the extreme end of the platform, where below a flickering light the great mail sack hung.

A mail sack is not a locked bag since they need little security.

Hold on, a mail sack's just landed on my lap.