That clock-like thing on the mast of the Arizona

[Razzbar]

What is that thing? It kinda looks like a clock, but if you
look closely, it's divided by 10 markings. You see it on
some pictures of the USS Arizona, looking astern from the
fore part of the ship, up on a mast or superstructure. I
was browsing an excellent recent book about the ship, and
none of the diagrams explained what it was. I've never
seen such a device on any other ship.

Know what I'm talking about?

[raymond o'hara]

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[ANDREW ROBERT BREEN]

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[Leadfoot]

Post by ANDREW ROBERT BREEN

Post by Razzbar
What is that thing? It kinda looks like a clock, but if you
look closely, it's divided by 10 markings. You see it on
some pictures of the USS Arizona, looking astern from the
fore part of the ship, up on a mast or superstructure. I
was browsing an excellent recent book about the ship, and
none of the diagrams explained what it was. I've never
seen such a device on any other ship.
Know what I'm talking about?

Range clock. Adopted by the RN Grand Fleet after Jutland, introduced into
US ships when they became a Grand Fleet battle squadron in '17 or '18.
It repeats the range set into the ship's gunnery director, while bearing
marks painted in the turrets show the bearing of the target. This allowed
ships which couldn't see the target (whether for fog, mist, smoke or
whatever) to dial the settings (plus the offset for position from the ship
they took the data from) into their gunnery control systems and hammer
away.

Did it work? and how effectively?

Post by ANDREW ROBERT BREEN
--
Andy Breen ~ Interplanetary Scintillation Research Group
http://users.aber.ac.uk/azb/
"Who dies with the most toys wins" (Gary Barnes)

[The Blue Max]

Post by Leadfoot
Did it work? and how effectively?

I believe it was highly effective in every post-Jutland WW1 fleet action...

:-)