If the object is a Model T Radiator Cap as Stathi suggests and which a quick Google search shows identical items, then there's a conundrum. For it to be a radiator cap, it has to be threaded otherwise the pressure would blow it off. Plus they're threaded by definition. But if the thing is ringed by concentric but not a spiral groove that would be the hallmark of threading, then it cannot be a radiator cap. Do check by running your fingernail around three complete revolutions and if it stays at the same elevation, then it's not threaded, but if it moves up or down, it is.

But the photos seem to show that the end that is threaded/grooved is tapered inward from the top of the grooves, making it more sleigh-bell in shape (but obviously not in function).

Lyle Browning, RPA


On Sep 24, 2014, at 3:22 PM, Kerry Gonzalez <[log in to unmask]> wrote:

> I know the picture may show that the lines are angled and would suggest threading but they are separate rings.
> On 9/24/2014 3:02 PM, Margie Akin wrote:
>> Hello everyone -
>>  I showed the object to my husband who is a retired steam-engineer.  He said that if it is threaded, which is hard to determine in the photos but he thought the lines were slightly tilted, it is probably a cap for a water or steam line. The "ears" (that what steam engineers call them) are there to assist attachment, especially if the threading is difficult.  He has seen examples that look like that on old equipment. If the example shown can be compared to the other one found, and they matched in terms of size and threading, it can be determined that the objects were manufactured for the same purpose - he said he would date it to the late 19th or possibly early 20th century.  Hope that helps --  Margie Akin - Riverside, CA
>>  ps. --a guacamole pot would have 3 legs, not four -but you knew that - I just couldn't help myself....
>>  
>>> Date: Wed, 24 Sep 2014 14:18:31 -0400
>>> From: [log in to unmask]
>>> Subject: Unknown Copper Object
>>> To: [log in to unmask]
>>> 
>>> Does anyone have thoughts on what this may be? It is a small copper
>>> alloy object with hollow legs. It is approximately 2 inches in diameter
>>> and 1 1/2 inches tall. While the exterior appears threaded we do not
>>> believe it was. We have considered censor, cap for some type of
>>> mechanism, and even joke about it being a small guacamole pot. We found
>>> this at a mid 18th-early 20th domestic site in Delaware and one was also
>>> found on a War of 1812 site (with some 20th century intrusions)  in
>>> Maryland.
>>> 
>>> http://s46.photobucket.com/user/kschamel/library/
>>> 
>>> thanks in advance,
>>> Kerry
>>> 
>>> -- 
>>> ******************************
>>> Kerry S. Gonzalez
>>> Lab Manager
>>> Dovetail Cultural Resource Group
>>> 300 Central Road, Suite 200
>>> Fredericksburg, Virginia 22401
>>> Office: 540-899-9170
>>> Fax: 540-899-9137
>>> Email:[log in to unmask]
>>> **WE HAVE OPENED A SECOND OFFICE! 2003 N. Scott Street, Suite B, Wilmington, Delaware 19806; 302-691-3216
>>