Next message: Jared Sherman: "Re: Refilling a compass, was: Compass tilt"
Jared wrote, in response to George:
> <Johnson's baby oil, straight from the bottle,>
>
> Johnson's confirm this to be simple mineral oil, with fragrence added.
> Generic mineral oil from the pharmacy is sold unscented, typically at less
> than half the cost. Of course, then the compass might not smell as sweet.<G>
I have a rather nice older, brass box-compass, less its box, picked up
for next to nothing at a flea market years ago. However, its fluid had
been drained off, making its card very unstable and the compass quite
useless as anything but decoration. Can anyone suggest how I should
determine whether it should be refilled with oil (Johnson's or
otherwise) or spirit?
I figure that getting a new box made would easy enough if I could refill
the compass itself. Maybe I would also need to restore the seals to keep
the fluid in. Still, the result should be prettier, better quality and
likely cheaper than buying a new compass of the same type.
This compass is identified as "Ritchie, Boston". It is marked in quarter
points but also in degrees, from 0 to 360. I assume that the latter
(rather than markings of 0 to 90 in each of four quadrants) dates the
instrument to post-1920 but perhaps American practice turned to the
360-degree notation before the British did (and/or perhaps my memory of
when the Royal Navy abandoned quadrantal notation is wrong).
Trevor Kenchington
--
Trevor J. Kenchington PhD
Gadus Associates, Office(902) 889-9250
R.R.#1, Musquodoboit Harbour, Fax (902) 889-9251
Nova Scotia B0J 2L0, CANADA Home (902) 889-3555
Science Serving the Fisheries
http://home.istar.ca/~gadus
