Expert: Bob Berry - 10/19/2011

Question
Hi Bob!

Got 2 insulators today when "scavenging".  I didn't know what they were until I searched "glass bottle tops".  Anyway, one is the common Hemingray 42, however, the "Hemingray - 42" mark is very light and is maybe "blotted out"?  Not sure how to determine this.  The other is a "W BROOKFIELD" "NEW YORK" but has a reverse  number 3 on the dome (CD 102, "Pony" style).  These things are awesome, I never knew!  I just bought them because I thought they were pretty!

Any help would be greatly appreciated.  I'm not trying to make any $$, I'm just interested.

Thank you so much!
Jen

Answer
Hi Jen --

Welcome to a great hobby!  There is a large variety of styles available in pin type insulators and collectors have developed a numbering system to identify the various ones called the consolidated design or CD numbering system.  Your first insulator (Hemingray-42) is a CD 154 and was a standard style for A.T. & T. for long distance telephone lines.  I suspect if yours is aqua it dates from the 1920s.  The light embossing is probably not a blot-out but just a mold that needed cleaning filling in some of the embossing.  These are pretty common with a $1.00 value or so for aqua and clear versions.  This insulator was made by the Hemingray Glass Co. out of Muncie, IN -- Hemingray was probably the most prolific maker of insulators being in business 100 years from the 1860's through the 1960's.  Your Brookfield piece is a CD 102 and dates from the 1890's.  Brookfield was based out of Old Bridge, NJ and was the primary insulator maker in the 1800's - they were the first maker of threaded insulators in 1865 went out of business shortly after WW1 in 1922.  This is a small style used for local telephone or telegraph lines.  This is also pretty common with a $1-$2 value.  Here are some links to help you learn more:

CD numbering system: http://www.nia.org/general/g_natpt.htm

General information: http://www.nia.org
         http://www.insulators.info

Price guide (excellent reference): http://www.insulatorpriceguide.com

         Thanks, --Bob