CREATE TABLE table_26840 ("Series" FLOAT, "Season" FLOAT, "Original air date" CLOB, "Production code" FLOAT, "Episode title" CLOB)

What date did episode 4 in the season originally air?
SELECT "Original air date" FROM table_26840 WHERE "Season" = '4'
SELECT "Original air date" FROM "table_26840" WHERE "Season" = '4'