"R.H." wrote in message
...
Just added another set:

http://puzzlephotos.blogspot.com/

If you haven't seen it already, over the weekend I added a scanned shot
from
an 1894 edition catalog, that verifies #313, the burner cleaner. It's on
the answer page to last week's post, thanks to Bill for sending that to
me.

Rob

Jeez, you have some great stuff in your collection, Rob.

I'll take a stab at some of them for the first time:

315. A set of skeleton keys.

317. A wooden Rubic's Cube?

308. Stair buttons for use on a framing square.

309. A drafting duck?

310. A pencil sharpener.

312. The same principle as that used in a lot of ancient Roman masonry: any
combination of blocks, looked at from below, has more than 50% of its weight
*behind* the edge of the block the stack is resting upon.

314. A Curta mechanical calculator.


--
Ed Huntress