Sean - what "50 year old threshold"?

----- Original Message ----- 
From: "Sean Dunham" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Friday, October 28, 2005 11:04 AM
Subject: Re: crown caps


>I thought this one had been tossed around before and there was a
> discussion on this topic in March of 2002 according to the HISTARCH
> archives.
> 
> Plastic liners were introduced in 1955 and gradually replaced cork
> liners (Lief 1965:40).  Another temporal nugget - a crown cap with a
> shorter "skirt" was introduced in 1956 (Riley 1958:272).  These two
> innovations make a nice cut-off for the 50 year old threshold.  If only
> I was looking at older assemblages more often ...
> 
> Lief, Alfred
> 1965  "A Close-Up of Closures:  History and Progress."  Glass
> Containers Manufacturers Institute, New York.
> 
> Riley, John L.
> 1958  "A History of the American Soft Drink Industry - 1807-1957." 
> American Bottlers of Carbonated Beverages, Washington, DC.
> 
> Cheers,
> 
> Sean Dunham
> 
> 
> 
> Sean B. Dunham, RPA
> Commonwealth Cultural Resources Group, Inc.
> Phone:  517-788-3550 / FAX:  517-788-6594
> e-mail:  [log in to unmask]
> http://www.ccrginc.com
> 
> 
>>>> [log in to unmask] 10/28/05 02:50AM >>>
> With regard to crown bottle caps, I have wondered if there was a  
> technological evolution of the liners? Although most have had cork
> liners during  my 
> lifetime, plastic liners began popping up recently and no doubt changes
> will  
> continue in the future. This makes me wonder if they always had cork
> liners.  Does 
> anyone know?
> 
> Ron May
> Legacy 106, Inc.
>