Does anyone know what this is

[Rob.]

As above, anyone know what this is or is called?

 

[Andy™]

quick google and its some kind of nautical pocket sundial

https://www.batela-giftware.co.uk/products/sundial?utm_medium=cpc&utm_source=googlepla&variant=4468201541&gclid=CjwKEAjwq5LHBRCN0YLf9-GyywYSJAAhOw6mX_hqYNPw7lBhvz_xhbi8eP1p9uGsmMclOKJe0-W6TBoCWFHw_wcB

 

[Rob.]

Thanks Andy. Googling "strange brass compass thing" wasn't throwing up much in the way of answers 

 

[Andy™]

image search

 

[Rob.]

I thought that only searched for the linked text behind the image? Didn't think a photo off my phone would help.

Learn something new everyday.

 

[Andy™]

not entirely sure how it works, but it brought up something almost identical, click a few links and see more about it and ended up with the above link

 

[sprocketflup]

Sundial Compass

 

[Tony S]

At a rough guess it can also calculate latitude. A rather fancy sextant.

 

[Rob.]

At a rough guess it can also calculate latitude. A rather fancy sextant.

It's not like any sextant I have seen as it doesn't have a 'viewfinder' 

I noticed whilst looking at it that there's a small piece broken. Been looking to try an find photos of where it goes which I seem to have found. Will start the search for instructions of use later tonight, more for curiosity than anything. 

 

[Evans Electric]

I see that the sun's shadow bit is lined up with noon  , guessing thats when they took a sighting ....other than that ... :C   Obviously a navigation instrument .

Some of those things were really clever .

I remember something about it being relatively easy to plot latitude but not longitude   ...or the other way around.   The other main problem was not having an accurate timepiece.