This month we will devote this space to multipart porcelain insulators. This continues to be an ever growing part of our hobby, even though some have thought in the past that these "boat anchors" would never "fly" with collectors. Those of us that are devoted multi collectors manage to find room for these long overlooked jewels. One thing that makes collecting multis fun is that they can be found almost anywhere. The following story is a good example of where these jewels may be found, and also presents an interesting idea of how to use them to best advantage.

Peter Hoffman sent in the following, which I am sure you will find interesting. Peter said: "I've only just received my second issue of Crown Jewels (Dec. 92 and Jan. 93), and have enjoyed your PIN article quite a bit. I thought I would share an anecdote about one of my multi finds. My wife and I went to an antique store in Flagstaff, AZ to see if they had any insulators. After picking out several glass and porcelain insulators, my wife pointed at something and said, "Isn't that an insulator?" Well, it was. It was the 12" diameter M-2927 sitting upside down, and it had the marking, "LOCKE/1055". The label said "Vegetable Tray", and it was marked down one-half price! The person working in the store told us that the dealer thought it was an ugly vegetable tray, and he wanted to get rid of it. Obviously, he had no idea what it was used for. This story has found much delight with our friends."

Unique vegetable tray (M-2927)

I thought that was a wonderfully funny story, and when I read Peter's letter to my wife, Kathy, she got a big laugh out of it, too. I have heard of using multis for candle holders, and chip and dip trays, but never thought to use one for a vegetable tray. Great idea! (?) Thanks, Peter, for that humorous story.

Jeff Kaminski (NIA 3582) has been aggressively tracking down multi parts that he does not have in his collection. He was very fortunate to acquire one of the mottled gray M-4395 Ohio Brass cross-tops at last year's London, Ohio show. These are very large and heavy insulators, and they are quite rare, too. When I published the book, Multipart Porcelain Insulators in 1988, I thought that this was the same insulator that was used on the Niagara, Lockport and Ontario line, in early 1909, to replace the M-3890's. I even used a photograph of this insulator in my book, which was from the March 31, 1910 AlEE Journal, to represent M-4395. However, when Ken Willick found a damaged specimen along the Niagara, Lockport and Ontario line, I realized that I had made a mistake, and assigned this "new" find M-4338. It exactly matches the one in the 1910 AlEE article. Ken's M-4338 specimen was marked "VICTOR", and it was much smaller than M-4395. He repaired it to a very nice display specimen, and

Jeff managed to talk Ken out of it. In Jeff s two photographs, you can easily see how different these two styles are. M-4338 weighs 33 lbs. and M-4395 weighs 52 lbs. Ken recently found, and pieced together, most of another M-4338 specimen. These two are the only known specimens of M-4338.

M-4338 on the left (14 -12 -10 - 5 x 13.5) and 
M-4395 on the right (14.5 - 9.5 -11.5 - 9.5 x 15.5)

Crown detail of M-4338 (left) and M-4395 (right)

M-4338 with Nicholson arcing ring 
(from March 31,1910 issue of AlEE Journal)

M-4338 was a unique design, which was developed to solve the puncturing problem in the lightning prone area along the Niagara, Lockport and Ontario line (see PIN in CJ dated November, 1991 for more details). M-4338 was specifically designed to be six inches shorter than M-3890. They found that the long, thin insulator shells, as in M-3890, could not resist the mechanical shock of lightning. Moreover, they discovered that short shells would allow a more even distribution of voltage across the entire body of the insulator; therefore, reducing the electrical stress on the inner shell, and thus reducing the chance of electrical puncture. The shells were made thicker, too, to resist breaking, and a fourth, recessed inner shell was added for additional protection against puncture; however, the inner shell probably was not needed. In short, the new four-part insulator was designed to flash over before reaching the stress level needed to puncture the porcelain shells. This was the first realization of the benefit to design insulators with a diameter to height ratio of less than 1:1. The new design (M-4338) was manufactured by the Locke Insulator Mfg. Co., and it was installed in early 1909 as a replacement for M-3890. The failures of tens of thousands of M-3890's on this line is why this style is so rare. A whole M-3890 has yet to be discovered, but Steve Jones has high hopes of finding all of the necessary parts. He only needs the second shell to complete a whole specimen. Good luck, Steve! 

M-4338 as shown in the 1910 Locke catalog

When the M-4338 was introduced, Ohio Brass decided to offer a cross-top style that was much larger, and without recessing the fourth skirt. This was the gray M-4395, and it was prominently marked on the side of the crown with a very large version of their embossed O-B marking. Note that I said "embossed". It seems that most collectors persist in using the glass terminology, "embossed", when most porcelain insulators are actually incuse marked (marking is recessed into the surface). Just like the stopped clock is right twice a day, the persistent use of "embossed", when describing porcelain markings, would be unknowingly right when describing O-B markings. In the case of M-4395, the O-B marking is about the size of your thumb.

I think that it was Ken Stefan who sent me the following drawing several years ago from an AlEE Journal. This piggy-back arrangement, with M-4395 on top, was used at railroad crossings. You may not be able to make out the numbers, but the drawing shows M-4395 with a top skirt diameter of 15" and the bottom insulator has a 17" top skirt. Note that the bottom insulator has a metal cap cemented on the crown, which has an attachment for the pin to support M-4395. I did not get all of the text of the article, but what was included said that this tandem arrangement was used on one 66 kV line. It was apparently designed to withstand voltage surges from lightning, to prevent the insulators from "spilling". There wasn't a problem with puncturing with these large, thick insulators. The electrical surge was the determining factor for insulation, not the normal line voltage. M-4395 evidently found limited use, since few specimens exist. 

A similar piggy-back arrangement has recently been reported by Ken Willick (NIA #3709) in New York. Note in the two photographs that both the top and bottom insulators are M-4395's. The steel pin in the top insulator is attached to a mounting bracket, which is apparently clamped to the crown of the bottom insulator.

Seven more M-4395's. Note the one mounted horizontally.

Bill Rohde (NIA #1219) reported a new find, but it is frustrating that he cannot find a way to add it to his collection. He has sent me several batches of photographs of this insulator, which, by the way, is still in service. We finally identified this unique style, and it has been assigned M4321C. I found a drawing of this insulator in the 1910 Locke catalog. If l remember correctly, Bill said that this is the only insulator like it along the many miles of this California line. That is all the information that Bill was willing to share -- that it was in California. Understandably, he keeps a close eye on this beauty.

M-4321C from 1910 Locke catalog

Locke M-4321C