Name the year for hercules
CREATE TABLE "1850_1871" (
  "class" text,
  "wheel_arrangement" text,
  "manufacturer" text,
  "year_made" text,
  "quantity_made" text,
  "quantity_preserved" text,
  "year_s_withdrawn" text
);
SELECT "year_made" FROM "1850_1871" WHERE "class"='hercules';