As I alluded to in the last PIN, a new and very exciting Fred Locke porcelain insulator has surfaced. It has a very interesting story and an old faded handwritten note to document where it was used. Mike Bliss said he got the insulator from someone in his extended family that has had it for about 20 years. We don't know who wrote the note. The note came with the Xerox copies of a page from the 1910 Locke catalog. From the look of the Xerox copies, I'm certain they were made in the early 1970's. Here is the complete text of the note:

This pin type insulator is a catalog No. 64 as shown in sheet 2800 of The Locke Insulator Mfg. Co. catalog of 1910. It was manufactured at the Victor, NY plant in 1905. For 34 years it was in service on a 23,000 volt system located in Honolulu, T.H. Sea coast exposure subjected it to salt contaminants. In 1939, this unit was removed from service and was returned to The Locke Insulator Co. then located in Baltimore, Maryland. Examination and test of this unit showed that it was in excellent condition being both mechanically and electrically sound. Since 1939 this insulator has been maintained as a museum piece.

That is essentially all we know about the insulator. It was removed from a line in Honolulu, Hawaii in 1939 and sent to the Locke factory in Baltimore where it was preserved as part of their history. Apparently the later owner of the plant, General Electric Co., removed all old pin-type insulators from the factory when the manufacture of pin-type insulators was discontinued in 1971.

We know from the under-glaze ink marking that it was not manufactured at the Victor plant in 1905. Under-glaze ink marked specimens were made by the Electric Porcelain Mfg. Co. in Trenton, NJ from near the end of 1897 or January 1898 to as late as 1900. EPMC was making only dry process porcelain insulators and converted to making wet process porcelain insulators with the help of Fred Locke. He had learned the technique from Imperial Porcelain Works and confirmed in John Lapp's experimental kiln in the summer of 1897 at Honeoye Fall, NY. Much more of the details can be found in my book, Fred M. Locke: A Biography.

New Fred Locke insulator, U-927, (shown on the far right) has #5-1 blue 
under-glaze ink marking. For comparison, U-927 is shown with 
U-939 (left) and U-927A (center).

Note that it is a 3-part glazeweld, which is composed of three shells fused together with glaze. The specimen is very well made with a top firing rest. The glazeweld joints are uniform as if extra glaze was used to fill in all the gaps. I will not repeat the discussion of the Thomas lawsuit against Fred Locke and EPMC for their infringement of the Boch glaze-filling patent. Usually glazeweld specimens made at Fred Locke's Victor factory show gaps in the glazeweld joint, but the glazeweld joint on U-927 is full of clear glaze used to fuse the parts together.

The earliest trade journal article I could find showing U-927 was one in the March 4, 1899, issue of Electrical World. The latest advertisement was one in the January 13, 1900, issue of Electrical World. The same photograph was probably used in all the ads. Note that it was shown used with a white porcelain pin base. Here is a similar photograph made with the U-927.

U-927 is shown complete with Fred Locke pin and glazed 
porcelain pin base. The Electric Porcelain Mfg. Co. at 
Trenton, NJ made both the insulator and the pin base for 
Fred Locke. The pin base has recess-embossed marking #1-3.

As a side note, Fred Locke designed steel pins with threaded wood cob and have the embossed marking on the top steel button, LOCKE'S / / PAT, in a circle as shown in the photo below. I have several pins like this. Have you seen this very early pin?

Below are photos from two of the trade journal articles. In the April 12, 1899, issue of Electrical Review, it stated, "Figure 2 shows a three-part insulator, fused with glaze, designed to carry from 20,000 to 35,000 volts, and which, it is said, will stand a salt water test of 80,000 volts. It is compact in form, standard in quality and of large capacity. The insulator is 7" in diameter, 4-1/2" high and weighs 3-3/4 pounds."

Fig. 2  3-Part China Insulator.
Electrical Review, April 12, 1899

The next two photos are from the March 4, 1898, issue of Electrical World. (next page) The text describes the insulator as follows, "Another three-shell china insulator is shown in Fig. 6. It is the No.4 style, and is recommended for potentials as high as 60,000 volts. There are said to be 20,000 of them in use. Its diameter is 7 inches, and weight 4 pounds." The "60,000 volts" claim must be a misprint. Don't think even Fred. Locke would claim that unrealistic service. An interesting note here is that after Fred Locke opened his own insulator plant in Victor, NY in the summer of 1898 and after he stopped having EPMC make insulators for him in the  first half of 1900, he replaced the No.4 Three-Part Porcelain Insulator with U-932. We showed this insulator in the last PIN in the April issue of CJ. U-932 was a bit larger at 7-3/8" in diameter. It was shown in his No.5 catalog published in August 1900. The inner skirts extended down a bit more than in U-927.

Finally, some of you may wonder about the assignment of U-927. It is shown in Jack Tod's Porcelain Insulator Guide Book. However, the drawing used for U-927 by Jack is not correct. From Jack's notes I knew the drawing was made based on a style shown in an early Thomas catalog. After researching Thomas catalogs, it became apparent that the drawing shown only in one Thomas catalog that Jack used to make the drawing was not accurate. The catalog numbers confirmed the style to be U-950, a two-part glazeweld. In CJ 1-80-32, Errol Bond reported having an insulator similar to U-927 except it was shorter and had the Imperial crown and wordy markings. In 1995, Errol showed me the specimen he reported. It actually is U-927C, but much shorter at 3-5/8" tall compared to the drawing for U-927C that is 4" tall. Bottom assignment of U927 is not valid. So, the reassignment of U-927 to the new Fred Locke insulator fit well in the U-Chart as a 3-part glazeweld.

U-927 was shown in the March 4, 1899, issue of 
Electrical World with Locke pin and porcelain pin base.