Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_63579 ( "Location" text, "Name of mill" text, "Type" text, "Built" text, "Notes" text )

### Question ###
What are the Notes of the Mill Built in the 19th Century?

### Accurate SQL ###

SELECT "Notes" FROM table_63579 WHERE "Built" = '19th century'