Table: ship_info
Columns: ship
date_commissioned
gross_tonnage
propulsion
material

Question: Name the sum of gross tonnage for wood on date more tahn 1846 for comissioned and ship of esk
SQL: SELECT SUM("gross_tonnage") FROM ship_info WHERE "material" = 'wood' AND "date_commissioned" > 1846 AND "ship" = 'esk'

Question: Tell me the sum of Gross Tonnage for isis ship on date commisioned less than 1842
SQL: SELECT SUM("gross_tonnage") FROM ship_info WHERE "ship" = 'isis' AND "date_commissioned" < 1842