CREATE TABLE table_26172 ("Warship" TEXT, "tons  (  L.ton  ) " FLOAT, "Horse- power" FLOAT, "Speed  (  Knots  ) " TEXT, "Armour  ( Inch ) " TEXT, "Main Artillery" TEXT, "Built Year" FLOAT)

How many different horse-powers does the Cochrane have?
SELECT COUNT("Horse- power") FROM table_26172 WHERE "Warship" = 'Cochrane'
SELECT COUNT("Horse- power") FROM "table_26172" WHERE "Warship" = 'Cochrane'