Context: CREATE TABLE table_name_75 (gross_tonnage INTEGER, ship VARCHAR, material VARCHAR, date_commissioned VARCHAR)
Question: Name the sum of gross tonnage for wood on date more tahn 1846 for comissioned and ship of esk
Answer: SELECT SUM(gross_tonnage) FROM table_name_75 WHERE material = "wood" AND date_commissioned > 1846 AND ship = "esk"