As Ed has already pointed out the artifact is doubtlessly a lightning rod 
insulator (LRI) [an insulating support for the conductor running from the 
lightning rod atop the roof to the grounding rod in the soil) and it 
probably was manufactured sometime between about 1869 and about 1890. Early 
LRIs were made of glass (ca 1850s-1890s) and were supplanted by ceramic ones 
in later years



Excellent webpage on lightning rod insulators (LRIs) manufactured in Ohio:

http://groups.msn.com/OhioLightningRodInsulatorsItems/



Photos of common types of LRIs (note especially the Otis type in the bottom 
row):

http://groups.msn.com/OhioLightningRodInsulatorsItems/idefinelriinsulatortypes.msnw



Photo of metal rings for mounting glass LRIs:

http://groups.msn.com/OhioLightningRodInsulatorsItems/mountinghardware.msnw?action=ShowPhoto&PhotoID=204



Photo of miscellaneous LR & LRI mounting hardware:

http://groups.msn.com/OhioLightningRodInsulatorsItems/mountinghardware.msnw?action=ShowPhoto&PhotoID=203



You may look-up the original U.S. Patent No. 94, 037 granted for this type 
of LRI to Franklin Scott of Brooklyn, N.Y. on August 24, 1869 here:

http://patft.uspto.gov/netahtml/PTO/srchnum.htm



Or . you may download images of the two paged patent document (the 
specifications page and a line drawing) from my webserver here:



http://skiles.net/94037_patent_specs.tif

http://skiles.net/94037_patent_drawing.tif


Bob Skiles
~~~
"Smithers! Get that bedlamite to an alienist." ~ C. Monty Burns


----- Original Message ----- 
From: "Ed Otter" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, November 09, 2006 10:45 AM
Subject: Re: Metal and Glass Artifact Identification


> Jeanne,
>
> Look at the top center image at 
> http://www.insulators.com/go-withs/photos/lris.htm.
>
> Ed Otter
>
> -------------- Original message -------------- 
> From: Jeanne Ward <[log in to unmask]>
>
>> We have been evaluating a site in Anne Arundel County, Maryland which,
>> according to records, was first constructed in 1820. Currently the site
>> consists of a basement constructed of fieldstone and the poured concrete
>> foundations of later additions. The structure was occupied through most 
>> of
>> the 20th century and burned in the 1960s. It was vacant/empty at that 
>> time.
>> Close interval shovel testing has resulted in the recovery of substantial
>> quantities of architectural metal (i.e. nails of all types) and little 
>> else.
>>
>> The point being - that we recovered two rusted iron ring-like things with
>> glass (now melted) insets. The exterior dimension of the ring is 2 
>> inches.
>> The interior diameter is 1 3/4 inches. The extensions for the nails are 
>> 1/4
>> inch. The wire nails are 2 1/4 inches. The glass appears to have been 
>> aqua
>> in color and quiet thick.
>>
>> My first thought is that they are lighting fixtures of some type but I 
>> have
>> never run up on anything like it. Assistance would be appreciated. Thank
>> you in advance.
>>
>> I have posted a couple of photos at:
>>
>> http://www.appliedarchaeology.com/page7.html
>>
>>
>> Jeanne A. Ward, RPA
>> Applied Archaeology and History Associates, Inc.
>> Annapolis, MD 21401
>> (410) 224-3402
>> FAX (410) 224-3470
>