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Note the spelling is “Dreyfous”, not “Dreyfus”.
This was Edouard Henry Dreyfous, who was a retailer (not a manufacturer) of antique furnishings and objets d’art from around 1880 through to the early 20th Century. French by birth, he settled in London but also had premises in Paris and New York. The London premises were opened in the 1890s at 104E Mount Street; moved to Grosvenor Square in 1899 and then to 30 Old Bond Street in 1913. He sold top end items produced for him by leading makers to wealthy clientele, including Queen Mary and Queen Alexandra among his customers.
Auction listings are a bit thin on the ground. His earlier and more elaborate offerings can be in the thousands, but your vases are fairly plain without the extensive engraving seen on the better pieces. The closest in broadly comparable quality (but of a more elegant design) was this one from 2017, which had a pre-auction estimate of £150-£250 ($174-$290) but failed to reach its reserve and wasn’t sold:
https://www.invaluable.com/auction-...-a-tall-ribbed-glass-vase-ta-382-c-8a84025bdd
I would think yours are probably early 20th Century and in the territory of £200 (~$230) for the pair. But they’re nice nevertheless and, at auction, you can never tell if someone takes a fancy to them.
[PS: I have seen items listed as being BY Dreyfous, rather than FROM Dreyfous with claimed dates as early as the 1860s but that doesn't fit with my understanding unless he was adding his mark to earlier pieces made by others].