Lightning rod insulators represent a fast growing area of insulator collecting, with auction prices reflecting the surge in interest. 

These little globs of glass (see color pictures on pages 39 & 40) are gaining popularity in the hobby due to their attractive colors and shapes, as well as their history. 

Lightning rod insulators (LRI's) are just that... glass objects that insulated lightning rods and grounding cables from the buildings they were mounted on. Some have large diameter holes through them so they fit over lightning rods, insulating the rods from the roof mounting brackets. Other styles had "slash" or "cross" tops. These were mounted along walls to insulate the grounding cable from the building, and were affixed to the building by metal brackets. Some had small diameter holes through them for the tie wire, and others used a wire groove for that purpose. 

In a web site¹, Roger Russell lists 329 patents that were awarded for lightning rods and their components starting in 1850. Lightning rods became big business by the 1860's, with salesmen finding ready customers in the midwest and eastern US who were willing to buy products to protect their homes and businesses from the real or imagined dangers of lightning. Drive through rural communities yet today and you still see thousands of lightning rod systems in use. Out west, where the threat of lightning isn't as great overall, lightning rod systems were never as popular. 

The lightning rod insulators on the following two pages are from Todd Grueninger's collection, and were photographed at the National Insulator Association's annual convention last summer in Springfield, Ohio. They demonstrate the wide array of colors that can be found in these jewels. Sapphire blue is a tough color in an LRI according to Todd, as he demonstrates in his "slash top" pictured in the upper left on the next page. The amethyst example shows the depth of color that can be found in some; and the mustard colored examples in the middle row represent another tough color. 

The emerald green LRI at the lower left is embossed Hickcok's Patent. The insulator has a slotted interior designed to fit a lightning rod invented by Russel Hickok of New York on March 29, 1859. In his patent description, Hickok wrote that his insulator design was improved over others because it was "a lightning rod insulator made in one piece, so as to support and insulate the rod, and also leave open spaces for water to pass through it, and for air, when suddenly expanded, to escape from within it."² Some sources suggest Hickok's glass insulators were manufactured by Canadian Glass Works. 

Other names embossed on LRI's include Spratt and Weston. Some items are believed to have been made by Hemingray. 

Collector Jim Colburn reports in another web site³ the he knows of 130 or more glass LRI shapes, and maybe twenty to thirty porcelain shapes. He lists known colors in dear, straw, peach, grey, SCA, purple, royal purple, milkglass, green, olive, jade, yellow-green, olive blackglass, emerald green, lime, cornflower blue, cobalt blue, fight cobalt, teal, ink, rootbeer amber, honey amber, blackglass, greenish amber, ginger ale, puce and more. The most common, as in other insulators, is aqua. 

In a "Pole Top Discoveries" auction this fall, a dark emerald teal green Hickock's Patent opened at $25, but sold for $121. An unmarked amber LRI of the same style as the purple one on the opposite page opened at $150 and sold for $242. And a tall "slash top" style in medium green opened at $120 and closed at $467. The success of such auctions leaves no doubt that LRI's have "arrived" as collectibles.

LIGHTNING ROD INSULATORS

Shown on the opposite page are additional lightning rod insulators in desirable, but not as bright, colors. Todd Grueninger says that when he finds LRI's, they are often still attached to buildings and painted over with many layers of paint. It's often not obvious what color the insulator is going to turn out to be.

The insulator at the bottom right of page 40 is a CD 132.4 Hemingray product embossed Patent / Dec. 19 1871. Even though it is a lightning rod insulator, it's listed in McDougald's price guide because it is a pin style insulator. That is, it has screw threads and fastened on a pin like a telegraph insulator. CD 132.4's were used in conjunction with CD 317's. The Chambers company used these much larger insulators for their special brand of lightning protection.

After attending the first national insulator show in New Castle, Indiana in 1970, I visited my brother, Tom, in Brookville, Indiana. Tom lived in a home that had been ordered out of a 1923 Sears catalog. But he lamented that his home was the only one in the neighborhood lacking a lightning rod system. So, my buddy Chuck Fox and I gathered up some Mickey Mouse insulators, some lightning rods off homes abandoned during the construction of a new reservoir, and fashioned a Chambers-style system. I returned to the home for the first time in 30 years this past summer, and was delighted to find our own version of the Chamber's system still in use. 

Our version of a wall mounted LRI was rather large. In this case, a CD 252 Hemingray. Notice that it is now splattered with paint. The year after we installed the lightning rod system, lightning struck the home. My brother, Tom, said he immediately ran out of the house and grabbed the ground cable to see if it was hot. He reported it was cool, convincing him that the system protected his house from damage. But I've always marveled at the fact that the home went almost 50 years without being struck by lightning, and then was struck shortly after a lightning rod system was installed!

References: 
1. http://home.earthlink.net/~rogerr7 /lightning2.htm 
2. http://www.nia.org/timeline/text/0023373.htm 
3. http://www.insulators.com/go-withs/lri.htm