Glass Discussion & Research. No ID requests here please. > USA

2 Glass Insulators

(1/2) > >>


I have just come back from my jaunt round the local car boot, and boy is it HOT :cry:

I have confused my poor husband by pouncing on these two insulators like a mad woman, with cries of "I know what these are"

One is Pyrex and is made in the USA, the other is Domminion, but that is as far as I go. I know someone on here is a colletor of these facinating  :wink: objects, and will come to my aid and enlighten me further.

Here they are, in all their glory, and undamaged. Mod: Dead link


Hi Barbara...

Your insulators are a long way from home!  The Pyrex is a CD 128 (that's the insulator collector's numbering system: CD = Consolidated Design), probably used for telephone lines.  Is it marked CSA or CSC?  C = Carrier circuit, S = Steel pin (smaller than the usual 1" old style), last letter = ???.  Real Pyrex boro-silicate glass.  They only come in clear and various light tints-- watch out for darker amber shades, they're irradiated.  The threads on the inside of the skirt are surely to increase the leakage path.  One fanatic has gone so far as to log all known mold codes, but this is rather around the bend.

The Dominion is a CD 154, Canadian, probably for [railroad] signal use.  These guys do come in lots of nice colors, amber shades in particular, which are still one of the best deals in colorful insulators to be had.  The rarest and sexiest color is cornflower blue, from lighter to an almost-light-cobalt shade.  You can see lots of the colors in my CD 154 gallery (I happen to specialize in these).  The CD 154 was the most popular of all designs; in particular, the Hemingray-42 was made by the jillion-- it's ubiquitous.

Both of these styles were copied by other countries, mostly in Central and South America.  There are some very pretty "foreign" CD 128s, but the foreign 154s are generally blah, with the exception of Zicmes (hand-made in Colombia in the 1960s in small numbers) which have perhaps the nicest color range of any manufacturer.  Also, there was an experimental 128 made by Hemingray in a very nice opal glass-- an attempt at salt-water resistance-- installed only in Florida.  Be careful with these, very soft glass, will dissolve in even mild acid!

And don't forget, two makes a collection-- now you're hooked!


Hi Ian,

The Dominion one is I think light peach glass, and there is the nomber 11 under the D in the diamond.

The pyrex one says

"Pyrex T.M. REG U.S. PAT. OFF.

If this means anything to you.


Like most things collectable, they come and they go. A few years ago Glass insulators were very hot and brought serious money at auction. A few months ago I was at an auction and the poor auctioneer struggled to get a few dollars for a box full of insulators. They have actually become a craft item, the crafters buying them and trying to figure out what to make with them. But here in Iowa, Telephone poles and their glass insulators are becoming a thing of the past. It seems like everything is now being buried underground and the poles are disappearing from the landscape along with old fashioned barns. Of course outhouses disappeared a long time ago and I am not sure there is anyone that misses those. Terry

Ian I just can't get over how good your site is. You get me interested in something which before I had given no thought to. Your presentation is excellent.
Looking at the CD 154 gallery  it almost makes me want to start collecting them. You have catalogued the colors just right with names that make sense and which I have used myself (ref here mainly to the ambers).

I'm surprised Barbara found any here as I understood from a previous posting by Bernard that mostly we have used ceramic in UK.

I can't help wondering why they bothered to make them in colors given that this is basically a ultitarian item. Could the colors be some kind of code in themselves ??

If not them I guess it must have just been for the brighten up the landscape which is great but extrordinary.


[0] Message Index

[#] Next page

Go to full version