I got a light aqua 151 smooth base .. minty ... under the fancy serif .... H G Co lettering, there is multiple round blot outs. Clearly visible is two capitol "A"s, an upper case "d" and the semblance of a top loop of a number 3 is barely visible. and not red arrowed . In hand the highlighted A A 3 figures are visible. ... PAT'd MAY 2nd 1893... This is a smooth base ins that was supposedly made before drips were patented .. why does the 1893 pat appear. The drip point date on an older smooth base insulator. ... I find perplexing
Paul GREAVES sez I think the answer is that it was not made before drip points were patented... in fact, I think it is quite likely that it was made after the patent expired, which would have been 17 years after 1893 (1910). It is also possible that Hemingray was getting enough orders for smooth base CD 151s (before the patent expired) that they intentionally had a few molds for use with smooth base mold parts. In that case, if they needed another mold for a production run (maybe one broke) they may have improvised by blotting out the embossing on an 1893 embossed one so they could fill the order they way they wanted to. I am not sure which might be correct really... but I think it is very safe to say this one was made after May of 1893!
Tim Baggett sez The Paul Greaves theory may be the answer. Someone may have needed another order of SB pieces. "Bubba" at the factory, got the mold and the base plate together. He then decided the date didn't need to be there, so he defaced the mold somehow. However, the deeper cut numbers remained. Just guessin"
BOB STAHR sez I would tend to agree with the second theory. I don't believe these are 1910 or after production. Those would have been made in stamped embossing molds, which do exist for this style, but have all been found with drips. I believe these were a special order in smooth base, made after the May 2, 1893 patent without drips and removed the patent info. Quality of glass to me indicates prior to 1900.