Can anyone shed any light on what this is?

[Kildonan]

This object was found on a shipwreck which sank in 1916 carrying munitions.

 

It might possibly be something to do with a 75mm gun. 

[Gardenerbill]

Could it be part of a pump?

[Chasemuseum]

Possibly the casing of a steam throttling valve.

[MikB]

Oil burner for ship's boiler? Would mean a very up-to-date ship for 1916.

 

Suspected cargo, or component of wrecked vessel?

Edited 15 January , 2019 by MikB

[Kildonan]

The cargo is French munitions. There are thousands of live 75mm shells. Also 8mm Lebel ammunition and the remains of Hotchkiss machine guns (the brass bits).

 

There are also what are possibly field guns and other items, still on iron wheeled carriages, with thin solid rubber tyres. It was found below one of these, so most likely part of the cargo.

 

It looks to me like some sort of exhaust or heat exchanger.