NavList:

-------------- Original message from Renee Mattie <ReneeMattie@HOTMAIL.COM>: --------------


> I believe I am finished translating the sheets on the top and bottom of the
> case.
> You can see it all at http://home.comcast.net/~reneemattie/navigation
>
> I think I have got the sense of the instructions. I don't mind whether
> "the carton at shoulder straps" is something that came with this compass
> or a common (at the time) phrase for some kind of backpack or satchel,
> though I am curious.
>
> I have never come within 1000 miles of the item, but it seems to be
> a standard compass with a decent sight, something like a cross between
> a more modern lensatic and a hiker's compass. It seems to have no
> internal dampening. It is up to the operator to dampen the oscillations
> with! a brake. I imagine this takes a bit of skill. The face is divided
> into
> 6400 parts, which seems a bit odd. The bearing is read from the map. The
> needle is held captive with a brake, the compass is set on the map with the
> immobilized needle aligned to the map's magnetic north, the edge of the box
> running through the sighted object or the current position, and the bearing
> is read from the map.
>
> The compass can be held sideways to measure the incline of a cannon, or to
> take the height of a distant object. This is the altitude part.
> One is to sight through the slit stem just as when one is taking an azimuth.
> The brass inclinometer needle is then viewed in the mirror.
> There is a graph on the back for figuring slopes (1 in 8, etc.)
> as well as height or distance off (depending on which is known).
>
> This is exactly the sort of little puzzle I am good at! , I suppose,
> and I have enjoyed scraping together my rusty French, some geometry,
> and my land navigation skills to figure out the 100-odd-year-old
> instructions on this obscure, outmoded, virtual device.
>
> Renee