thanks m. I'll admit freely that I have virtually no knowledge of Continental bottles, and in particular decorated coloured ones with matching Nos. applied by means of enamelling - so certainly wouldn't presume to disagree with Ms. Cecilia Nordstrom (apologies for the missing accent mark)

I suspect we've digressed a little from the original subject of 'engraved numbers' - and quite happy to accept that for whatever reasons there are different chronologies at work here regarding whether the applied Nos. are enamelled, engraved and/or country of origin.
It's also worth remembering that most of us here, for whom English is a first language, have a tendency to think automatically of features of British made bottles - such an easy trap to fall into when discussing almost anything historical.
Think I said a long time back, that to some extent it's possible to suggest a rough estimation of period of manufacture from the type of script or font of the engraved matching No. Certainly in the U.K., the Victorians were very keen on their Nos. being largish and slightly florid,
a habit that went hand in hand with their copperplate script and a leaning toward alphabet letters with substantial serifs - features that remained popular until well into the C20 until the advent of fonts such as Gill Sans.
As these things progressed through into the C20, our writing habits leave behind much of this C19 embellishment, both in size and decoration, and appear more plain.
Still waiting for someone/anyone to provide pictorial assistance - do I recall a certain Moderator who has a substantial collection of bottles
