Last November, we presented six new styles for the U-Chart: U-196 (Fred Locke) , U-706A ("CENTRAL"), U-972, U-984, U-987, and U-989. The last four are threadless. This month, we will show five more additions to the U-Chart.

For those of you that may not be familiar with the U-Chart, this is the numbering system for unipart porcelain insulators, which was developed by Jack Tod in 1971. Jack's 3rd edition book, Porcelain Insulators Guide Book was published in 1988 (see ad in back of this issue for ordering information). Since that time, 29 new unipart styles have been reported, which make a total of 1022 styles. Actually, there are 3-4 more than that now, which we will talk about in a future issue. Last Fall, I published a four-page 1992 U-Chart Supplement, which updates the style drawings for Jack's book. If you will send me a legal size SASE and $1.00, I will send you a copy of the supplement. The supplement will conveniently fit inside your 3rd edition book, without hanging out, where it will always be easy to find.

Many of you know Bill Rohde and his fantastic porcelain collection, most notably his multipart collection. A couple of years ago, Bill reported a very unusual porcelain insulator, which we have been very late in reporting. This new unipart style has been assigned U-372. I had a difficult time trying to decide where to put it in the U-Chart, since it was not like anything else ever reported. As you can see, the shape of this insulator is very close to the glass CD 282 Hemingray No.2 Provo and the CD 283 Hemingray No.1 Provo. The CD number drawings are shown courtesy of N. R. Woodward, as shown in his book, The Glass Insulator in America -1988 Report (see "Reference Library" page under Albers for ordering information.)

Unmarked Pittsburg U-372

It is not surprising to learn that Pittsburg made U-372. Pittsburg was famous for making very odd styles, in an apparent effort to capture business, no matter how small the order. Odd shapes were their specialty, which could easily be made in 2-part molds. Many of their simpler shapes were also made in 2-part molds, which eliminated the need for a trimmer operator to cut the wire groove. However, the use of 2-part molds produced a quality problem, which did not seem to concern Pittsburg. If you are familiar with Pittsburg unipart insulators, you undoubtedly recognized that quality was of little concern to them. Multipart insulators seem to be the exception. since high voltage has no mercy for cheap, poorly made insulators. Perhaps, if they had been more concerned with the quality of their unipart insulators, Pittsburg would have lasted longer in the business, but they would not have made near the number of insulators during the eleven years that they were in business. 

When the clay is pressed in a 2-part mold, with great pressure, some of the clay squirts through the two mold halves. The resultant mold line equally splits the shape of the insulator. Where the clay was squeezed out along this mold line, the long, microscopic, clay particles align them. selves with the mold line. This makes the insulator susceptible to fracturing along the mold line. Some Pittsburg specimens, with pronounced mold lines over the top, can easily be split in half with a blow to the top of the crown. I have seen some specimens that even had a small crack somewhere along the mold line, which developed when the insulator was made.

Pittsburg evidently had an obsession about not wanting to lose a sale for lack of a design that the customer wanted. Even though they made many more styles than their catalogs showed, their catalogs still contained a plethora of styles. For example, their 1918 catalog lists no less than nine "hat-shaped" double petticoat styles, some of which differed from others, only because of a slightly different crown radius. Also, they listed six different pony or semi-toll styles. While other companies cataloged only the more popular styles of each voltage class, Pittsburg went out of their way to make special designs for their customers. They essentially operated a "short order business" for insulator customers. 

This next Pittsburg style is another example of them copying popular glass styles. Fred Collier has kindly loaned me his undated Pittsburg catalog No.2. This could very well be the only Pittsburg catalog that has survived. I would guess that it was published circa 1912. As you can see from the full-page reproduced here, the insulator is a porcelain copy of the Barclay insulator, which is identical to the glass CD 147. A specimen of this insulator has never been found, but I am reserving the style number, U-147, if it does appear. Surely, if one of you had found a specimen of this style, then it would have been reported. But then, the "Provo" U-372 was rather unique, too, and it was not reported until recently. Keep looking!!

Unmarked U-956

James Colburn reported an early, classic two-part, glazeweld, which we have assigned U-956. Due to its small size, this insulator looks quite common when it is mixed in with other insulators on a sales table, That is why James decided to place it under a glass dome at the Orlando National. And, yes, it did attract a lot of attention. This unmarked insulator appears well made. I would guess that it was made by Thomas before 1910; however, I would not rule out New Lexington. It does not have any characteristics that would allow a good guess, other than the fact that only Locke and Thomas used the glaze-welding technique, with the exception of a few styles made by Pittsburg, and at least one style made by New Lexington (U-966A).

The next three new styles are Fred Locke insulators. The first one is the two-part, glaze-weld style, U-941B. Three of these have been reported. They are all white with the Fred Locke under-glaze ink marking #6-3. Based on the last patent date in the marking, June 7,1898, these insulators were made after that date, and before Fred's next patent, dated May 29, 1900. Robin Harrison reported the third specimen. The first report of this glaze-weld insulator was made by me in the January, 1985 issue of Crown Jewels of the Wire. At that time, we called it a U-610A, but it really needed a new U-number, since it is a glaze-weld, and an early classic. U-941B is the predecessor to the Fred Locke U-610A and other similar cable-top styles.

U-941B with Fred Locke under-glaze ink marking #6-3

As will be discussed in my upcoming book, which will be a biography of Fred Locke (maybe available later this year), the under-glaze ink marked Fred Locke specimens were not made by Fred. We now know which company made these glazeweld specimens for him, and it was not Imperial! The name of that company will be revealed in the book, along with a detailed history of Fred' s family, how he started jobbing electrical supplies in 1892, his short-lived partnership to sell his patented pins and glass insulators, his jobber business selling porcelain insulators (made by three different companies), why he sold the Victor factory, and much more. So much new information has been uncovered recently, that it has caused the entire history of Fred Locke to be rewritten. 

The second new Fred Locke style is U-969. This insulator was reported incorrectly as M-2335, in the September, 1990 issue of Crown Jewels of the Wire. I recently saw this one-of-a-kind insulator. I was amazed that it was actually a two-part, glazeweld, rather than two parts cemented together, and it had only one spout, instead of two! It has a crackled, dull white glaze, and marking #6-2. As with M-2335 (2-spouts) and M-2795 (1-spout), U-969 has a raised ridge, or eave trough, around the outside edge of the top skirt, and one spout. This design was to allow the rain to collect on top, and drop to the side of the crossarm from the spout, instead of splashing on the crossarm, wetting the underside of the insulator. This design proved to be of no benefit. Dirt would collect on top of the broad top skirt, contributing to surface leakage during wet weather.

U-969 with Fred Locke marking #6-2

The third new Fred Locke is U-957A. The glaze on this only known specimen is very dark tan. There is a weak # 7-1 marking on the top skirt. This insulator is a cousin to U-957, and has a skirt that is more than one inch longer. This long-skirt style was made to conform to Fred's patent No. 852,730, granted on May 7, 1907 (patent application filed on November 16, 1903). The patent claimed the long, slightly flared skirt, which would maintain a uniform distance from the pin, and ultimately rest on the crossarm. Even in rainy weather, this design was claimed to provide a dry area inside the bottom skirt and around the pin. By keeping the pin and inner surface of the insulator dry, it was claimed that the chance of electrical leakage to the pin, during wet weather, would be greatly reduced. It is unfortunate that the single specimens of U-969 and U-957A probably will never find their way into collector's hands.

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U-957A with Fred Locke marking #7-1