Boatswain's Whistle for battleship HMS Revenge? - Please confirm

[leproc]

Hello!

A seller has a boatswain's whistle that bears the mark of Revenge BO along with a Made In England stamp.

I think its authentic, but I have two questions:

-Is this whistle from the battleship or from the more modern submarine? In other words, is the design of the boatswain's whistle in line with WW1 or WW2 design?

-What does the BO mean on the side of the whistle?

Thanks!

[peter monahan]

The first thing that comes to mind for 'B.O.' is 'Board of Ordnance', whch was stamped on most British military equipment for well over a century.


’AVE you ’eard o’ the Widow at Windsor
With a hairy gold crown on ’er ’ead?
She ’as ships on the foam—she ’as millions at ’ome,
An’ she pays us poor beggars in red.
(Ow, poor beggars in red!)
There’s ’er nick on the cavalry ’orses,
There’s ’er mark on the medical stores—

Rudyard Kiplng, 'The Widow at Windsor'

I also suspect, but don't know for sure, that bosun's whistles have not changed in the last 100 years in the RN.

[dragnet]

Here's a rather ornate one i picked up last week.

[peter monahan]

That's a nice one, Dragnet! And BO marked too. Must have been for a CPO or some such.