What does the above photograph commemorate and document?

That's  the Ruin's of Gallego Flour Mills
 It records an event and exists as an allegory of the costs of the Civil War. Back then the Gallego flour mills were world renown and symbolize the economic strength of united states due to superior flour it produced. No-one ever thought that it would be destroyed by our own.

Trumpets, saxophone, trombone, flute, french horn  mostly in jazz or classic.  you can answer the rest thats on your own honestly 

If you could give us the questions i can see if i can you! : )