Purple Pamona CD 244 a study

By Mike Spadafora; posted November 9, 2017

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CD-244 a study... This insulator is NOT mine. It is being delivered to Paul Greaves for fracture repair . I decided to take some photos of it and examine it very closely as I may never have the chance again to look at one up close like this. This piece, known as the "Purple Pamona" was used on the early single phaze1893 AC system in Pamona California constructed by Westinghouse. only a few are known to have survived . The piece was produced as a proprietary product for early 1890's Westinghouse AC systems and not openly sold on the marked as far as I am awair . This piece is one of the "holy grails" amongst CD collectors. The owner can come forward if he wishes.

The CD 244 is an utterly unique piece in how it was manufactured. There is NO mould line on the outside bell whatsoever. There is a mould line circling the crown just below the cross grooves . Another mould line also circles the bottom of the tie wire groove and mould lines splitting the tie wire groove in half . The inner skirt appears to have moulded completely separately from the main insulator and inserted into the body wile the glass was still molten hot . The quality of the glass is incredibly good for it's time (1893). There are virtually no imperfections air bubbles or inclusions that are detectable . The threading mandrel was inserted very poorly and the piece is nearly thredless with badly misshapen threads . Lastly, the piece was formed in a very well made mould set with very high quality machining work and pressed with rather high pressure . The skirts are VERY thin more typical of glass plates and dish ware of that era .

Clearly this insulator was manufactured by someone who was not in the practice of making insulators . My suspicion is it was made in a glass house known for high quality bottles and glassware that did not have the proper equipment to press a product like an insulator. It would be interesting to research what glass houses were nearby the Westinghouse factory in 1892-1893 that also made dish ware, lamp globes and products of this nature. Westinghouse was selling a lot of arc lamp gloves and parts at this time in history as well as needing glass plates for meter windows etc ...