CREATE TABLE table_63579 ("Location" CLOB, "Name of mill" CLOB, "Type" CLOB, "Built" CLOB, "Notes" CLOB)

What are the Notes of the Mill Built in the 19th Century?
SELECT "Notes" FROM table_63579 WHERE "Built" = '19th century'
SELECT "Notes" FROM "table_63579" WHERE "Built" = '19th century'