I did a quick search here and all the pictures in all the relevant posts no longer show (thank you photobucket).
From what I have read, the HS info is as follows:
S67 - Brass case (67% copper)
S - manufacturer (Königliches Munitionsfabrik, Spandau, Germany)
9 - case lot number
15 - year of loading (1915).
How did I go?