Statue of Ludovisi Ares. Source: http://commons.wikimedia.org/wiki/File:Ares_MK1888.png
This image comes from the 4th edition of Meyers Konversationslexikon (1885-90), it is therefore Public Domain.
Uploaded to Wikimedia Commons by user Maksim. Converted to SVG by Warszawianka.
Took Johnny Automatic's benfing child scan and conversion, converted it back to a bitmap, erased the border and background, then converted it back to vector.