CREATE TABLE table_40494 ("Name" TEXT, "Built by HM Dockyard" TEXT, "Ordered" TEXT, "Laid down" TEXT, "Launched" TEXT)

What was launched and laid down in February 1819?
SELECT "Launched" FROM table_40494 WHERE "Laid down" = 'february 1819'
SELECT "Launched" FROM "table_40494" WHERE "Laid down" = 'february 1819'