Height & Fuze Indicator - Information Required

[Stumpy600]

I've recently acquired this tripod top? (It may not be a tripod at all!).  that took my interest.  It's post WWI and its very different to the height/fuze indicator for AA use shown in any WWI photos.  It's unlike anything I've come across before.  Being made in 1925, only seven years after WWI, it's certainly got some age to it so earlier examples could possibly have seen WWI service.   I think it's incomplete as the knurled circular top lifts out of the base.  There is a threaded hole in the base of the shaft that tells me something was attached.  The bearing ring moves freely and is knurled for its lower third.  The knurling on both would indicate they were both rotated by hand.  Newman & Guardia were primarily involved in manufacturing cameras & sextants, with some involvement with aircraft instrumentation.  I have searched the web & found absolutely nothing about tripods/artillery instruments etc. relating to them.  Has anyone seen one of these before?  Any suggestions most welcome as well!  The circular top has four countersunk holes that would indicate there was something bolted onto the top.  I'll carry on trying to research it but all input greatly appreciated!  The top circular piece is stamped as per the photo.  It is wholly made of brass & weighs about 2Kg.  When I obtained this the three 'mounts' were the other way round & much further opened.  I reversed them & closed them up to make the unit stand upright!

Edited 21 December , 2019 by Stumpy600
Additions to text

[peregrinvs]

One sold on eBay last month. The seller gives some details:

 

https://www.ebay.co.uk/itm/WW2-ROYAL-ARTILLERY-GUN-CREWS-039-HEIGHT-amp-FUZE-No2-Mk11-039-ADJUSTING-INSTRUMENT-/223727548744?ul_noapp=true&ul_ref=https%3A%2F%2Frover.ebay.com%2Frover%2F1%2F710-53481-19255-0%2F1%3Ficep_ff3%3D2%26pub%3D5574735181%26toolid%3D10001%26campid%3D5336086427%26icep_item%3D223727548744%26ipn%3Dpsmain%26icep_vectorid%3D229508%26kwid%3D902099%26mtid%3D824%26kw%3Dlg%26srcrot%3D710-53481-19255-0%26rvr_id%3D2230362611038%26rvr_ts%3D2a09699216f0ac3cf9e6f604fff14e46&nma=true&si=JfBxY6mFumbDZ1oxvkiIJKucuoA%3D&orig_cvip=true&nordt=true&rt=nc&_trksid=p2047675.l2557

[Stumpy600]

Thanks for that!  The one I’ve got was that one!  Since getting it I’ve dismantled & restored it.  The info that was provided wasn’t necessarily accurate I think.  It’s obviously incomplete and I think formed part of something more comprehensive as it has a bearing ring which doesn’t really add up to the inscription on the top referring to height & Fuze.  All very confusing!

[Stumpy600]

These two photos are of the HFI in common use during WWI & bear no similarity to the item I have.  Things must have moved on fairly rapidly!  My item can't have anything to do with the Wilson & Dalby detector either (different manufacturer!)