CREATE TABLE table_54825 ("Home team" TEXT, "Home team score" TEXT, "Away team" TEXT, "Away team score" TEXT, "Venue" TEXT, "Crowd" FLOAT, "Date" TEXT)

When did essendon play away?
SELECT "Date" FROM table_54825 WHERE "Away team" = 'essendon'
SELECT "Date" FROM "table_54825" WHERE "Away team" = 'essendon'