Classic windmills

From a collection of photographs of Russia at the turn of the century, an image of one of the earliest types of windmills. Photographed in rural Ialutorovsk county in Western Siberia, these wooden windmills were designed to grind grain rather than draw water. I presume the grinding stones are inside the base, and since I don't see a vane, I would guess these must have been turned by hand to face the prevailing wind. There are a number of other interesting photos at the primary link.