The second invasion of the Peloponnesians was prolonged for forty days, and the whole Attic territory was laid waste. Pericles again refused to venture a pitched battle against them, knowing well that the Athenian army was no match for them in the open field. But a powerful fleet was sent to cruise round Peloponnesus, which inflicted much damage on the coast districts. It was a welcome relief to the Athenians selected for this service to escape for a time from the plague-stricken city; but unhappily they carried the infection with them, and the crews were decimated by the same disease.