Steampunk PDA

Steampunk PDA

Brass Goggles just hipped me to this great site for anachronistic gear, Jas Townsend & Son. This pocket notebook is made of brass and ivory, and is... well I'll just let the Townends tell ya:

It's the 18th century version of the PDA. Beautifully crafted here in the US. Based on an original that Jefferson owned. These are made of sturdy brass stock with 4 old ivory pages and a pencil. Use this for making notes in the field and just erase with a wet finger when you are done. Folds up into a nice small package 1-1/8 inches by 4-1/2 inches by 3/16 inch thick. No batteries needed.

I'm curious about the stylus for this, is it a piece of graphite sheathed in brass? It looks like from the photos, the stylus slide through the curls of brass and locks the unit. Also, I'm hoping that by old ivory, they mean the ivory is recycled. Of course this doesn't seem like an intricate design, and Jes has a stash of old ivory keys from some old pianos which seem like they'd be just about the right size...