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This is a photograph of an Ice Blue HEMINGRAY-42 with round drip points that was discovered recently. However, what was discovered was not the insulator, but just this slide of the insulator... The actual specimen was last seen in the early 1970's. Although the quality of this image is poor, you can easily tell this is no normal CD 154! There is absolutely no bottom wire ridge at all!
CD 154 HEMINGRAY-42 was introduced in 1921 to replace the CD 152 HEMINGRAY No 40 as the standard telegraph insulator. CD 154 has a wider and much more square wire groove, to better accommodate the tie wires. CD 155 HEMINGRAY-45 replaced the CD 154 in 1938. The main difference between the CD 154 and the CD 155 is that the CD 155 has a much stronger lower wire ridge; one that drops down vertically for about 1/2 inch, before the normal taper of the skirt.
It is clear that this specimen was retrieved from the Hemingray dump, because of the damage and cement on it. It is also quite likely that it was an experimental design for a CD 155, although, on this unit, there is really no lower wire ridge at all, and there is a nearly vertical slope from the lower part of the wire groove down to the base of the insulator. Lots of glass in this piece!
The Ice Blue color, and a date code that starts out with 0-4, probably dates this insulator around 1935. However, one can imagine in completing the final design for the "stronger lower wire groove" CD 155, that the Hemingray company realized that they could remove some of the excess glass and return to a more convex skirt, while maintaining a strong, square, lower wire ridge.
At the moment, all this is educated speculation on my part. It is hard to say if this piece surfaces again, if it would get a new CD number. Initial feedback I have heard indicates that it would not. I don't know if it would be classified as a CD 154 or a CD 155. New CD or not, it is still a interesting HEMINGRAY-42!
Brought to you first on the World Wide Web! Copy of the slide provided by John and Carol McDougald .
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Last updated Sunday, August 27, 1995