Is there any information of this sort pertaining to insulators in  
Australia? Not so much lightning rod insulators, as telegraph wire  
ones. Were glass insulators replaced (through time) by ceramic in Oz  
too?

Graham Knuckey - [log in to unmask]
....................................................
Psalm 15



On 10/11/2006, at 4:41 am, Bob Skiles wrote:

> 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
>
>