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Porcelain Insulator News
by Elton Gish

Reprinted from "Crown Jewels of the Wire", January 2000, page 12

The first insulator we will report this month is one I acquired a few years ago. The crown is unusual in that the cutout under the cable groove is pointed. At first I thought this was a new style but a search of the U-Chart showed it to be U-570. The drawing in the U-Chart does not show the crown detail because it was taken from a catalog drawing. James Lindsey, Jr. (NIA #3750) reported two U-570's one of which was marked THOMAS on the crown. Bill Rohde (NIA #1219) also reported a marked U-570 on the survey for the Value Guide and a few unmarked ones were reported, too, by other collectors. Two or three unmarked U-570's were at the Scottsdale National and London show this year. I suspect that the crown was cut out this way to accommodate a metal clamp device to hold the conductor. James agreed with the idea of the crown clamp. He said one of the U-570's he found was mounted vertically on a pole. He thought it may have been used in a dead-end service and a crown clamp would have worked better to support the conductor. 


Thomas U-570 with unusual crown detail.

Jarl Anderson (NIA #755) sent some nice photos of two interesting insulators he recently acquired. I mistakenly thought we had previously reported this first insulator. Ben Kirsten was the first to report M-2321. Ben and Jarl apparently found several damaged M-2321's on the same line in southwestern Colorado. All of the M-2321's had a cast iron Smith Grip pin cemented in the pinhole with a large U-bolt that secured it to the crossarm. The insulators are unmarked but the characteristics indicate they were made by the Lima Insulator Co. (1904-1908). Unfortunately all of the insulators Ben and Jarl found were damaged but they still make nice specimens as you can see in Jarl's photographs. There is an embossed marking on the fluted sides of the cast iron pin: PATENT / AP'D FOR / SMITH / GRIP. The bottom of the Smith Grip pin is slightly concave and has two extensions that grip the crossarm so the bracket will not turn. William Smith was granted patent No. 878,679 on February 11, 1908 for this unique pin.


M-2321 mounted on a Smith Grip pin.


M-2321 showing complete Smith Grip pin assembly. 

Jarl said he found an unusual spool-type dead-end bracket in southern Maine on a downed pole along a railroad track. I looked through a number of catalogs and could not find this specific bracket. The solid porcelain spool insulators are designed with extensions on each end that fit into the round holes in the bracket and held securely when it is bolted together. The bracket was bolted at a right angle to a crossarm by means of the long bolt in the center. Apparently the brackets were used in dead-ending service. Jarl found four brackets with medium and dark brown spools. The medium brown spools on two of the brackets were unmarked. The dark brown spools were marked with "U" inside a circle on one end and the Line Material marking on the other end. The Line Material marking is a "LM" inside a triangle that is inside a circle. The "U" marking was used by Universal Clay Products Co., Sandusky, OH which made the insulators for Line Material.


Unusual dead-end Line Material bracket with solid porcelain spools.

Dennis Stewart reported some very nice old multipart porcelain insulators in the past and he continues to make some interesting reports. Some time ago he sent me photographs of three very old classic multiparts that you will find interesting. The first one is M-2154 that was made by Pittsburg in the 1910's. This is a very small multipart with a lily-shell bottom skirt. The glaze color is dark but the top skirt is lighter with a pretty speckled glaze.


Unmarked M-2154 made by Pittsburg.

The next insulator is M-2636 that has a nice long lily-shell bottom skirt and a curved petticoat under the top skirt. What makes this one so unusual and rare is the incuse marking on the side of the crown: JOHNS-MANVILLE. These were made by the New Lexington High Voltage Porcelain Co. (1903-1912). The marking is very rare on multipart porcelain insulators. All of the multiparts I have seen with the Johns-Manville marking have an odd, slightly mottled, brown glaze similar to German chocolate. It is not particularly attractive but the rare marking and classic lily-shell style more than make up for it. The glaze on Dennis' M-2636 appears prettier than most J-M multiparts AND it is one of two M-2636 known with that marking!!!


One of two known M-2636's with JOHNS-MANVILLE marking.

The last photograph that Dennis sent is of his unmarked M-2635. I wish you could see the beautiful tan glaze. It appears as though either Lima or Fred Locke could have made it and I would guess circa 1904-1905. I have an M-2635 that has a much darker, finely speckled glaze and a small incuse "Y" under the top skirt. I don't remember seeing a multipart insulator with this letter marking but two specific styles of unmarked Fred Locke unipart insulators (made after he left the company in late 1904) have letter markings. White U-379's have small incuse or "Z" on one of the ears and white U-380's have a small incuse "Y" on one ear. Hugh Barbour reported an incuse "L" on unmarked Fred Locke U-192A's and at least one U-964 he found in British Columbia. I also have a U-964 with the "L" marking under the top skirt.


Beautiful unmarked M-2635 has a light tan glaze.

 



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