good points:
1. Yes they are consecutive paragraphs, I literally copied and pasted, hence the first paragraph not really having anything to do with cameo glass, to show that they follow on from each other.
One of the reasons I did that was because the author does not denote or mention time frame between the first paragraph where she mentions 17th century, and the subsequent paragraph.
The book was written in I think 1912 so it's reasonable to assume the glass she discusses in the second paragraph was made between 17th century and 1912. (To me, from what I have read in many other books etc, it is obviously referring to glass made in the 19th century though).
Perhaps she doesn't mention time frame because she is unsure whether it actually is 19th century or 18th century. The Chinese were making cameo glass in the 18th century iirc (need to check that and give a reference).
The second reason was to demonstrate that it appears to me, the first paragraph is all about engraved glass, and the second paragraph was about a different method i.e. cameo glass.
The reason I think, that it reads oddly, as it is in the context of her doing a Chapter on glass within a book of various decorative techniques. So she is skimming the surface of French glass, English glass, Bohemian glass etc. rather than it being in any detail. However she has seen fit to describe two specific processes of Bohemian glass that are outstanding, i.e. their early engraved glass and then bas relief and cameo overlay glass.
2. 'And another possible confusion is the use of the term "cameo incrustation" ... which was a British term for "Sulphide" [Apsley Pellat, etc.].
Interesting point.
I think she was discussing three processes that all come under the banner of cameo glass or bas relief carved glass, as opposed to engraved glass where there is no relief layer on the picture and the engraving is 'cut' into the body of the glass. And I think she used process 1 and process 2 to describe the execution of appearance of process 3:
'Many Bohemian pieces showed an original decoration in the way of ornamentations in relief on the outside (process 1. To me this would be bas relief carved pieces (where there is no overlay glass and the carving is on one layer of glass only, or where there is cameo cut from one colour glass to a interior layer of a different coloured glass), whether the decoration was all over the body of the piece or just in a specific 'medallion' on the vase/goblet (medallion in this case denotes a large delineated oval cartouche where there is a bas relief or cameo carved scene within it) ,
while the art of cameo incrustation was also first used by Bohemian workers (process 2. To me this would be the incrusted (ceramic) cameos on the outside of goblets for example ),
who sometimes varied it to obtain odd and pleasing effects by engraving through an outer casing of colored glass into an interior of white, transparent, or enameled glass (process 3. e.g. my decanter, or the goblets such as those that are overlay or double overlay glass ( example in the Corning of the ?Karl Pfohl lidded goblet) and have carved a scene of some sort in what is called a 'medallion' on 19th century Bohemian glass).
One such specimen, a salt cellar, is shown in the Mitchell collection.' Rather unfortunately whilst there are examples shown, this particular one is not. Also unfortunately, it is a salt cellar. Which means it could either represent a cameo incrustation with the incrustation in the base (in the likeness of a cameo incrusted sulphide paperweight I guess) or could be a piece as I have described for process 3. with the piece double or single overlaid and cameo engraved.
I thought of it as being a cameo piece rather than a sulphide with overlays cut to clear on the outside of the piece, because she used the word 'engraved' rather than cut.
Hmm, so I think the entire paragraphs describes cameo glass (i.e. bas relief carved glass much in the way a cameo is traditionally in relief against a background of flat surface), which is why she included cameo incrustations, but her use of the actual word 'cameo' might, as you say, refer only to cameo incrustations i.e. sulphides.
Ok, so she is may not specifically be calling Bohemian mid 19th century cameo glass, 'cameo glass', but she is at least referring to Bohemian mid 19th century cameo glass, which is more reference than I have been able to find elsewhere in other books. Hence my comments earlier in the thread berating the fact that Roman, Chinese and English cameo glass is discussed but querying where was the acknowledgement of the Bohemian mid 19th century cameo glass which was so extraordinary (different to other glass at that time, and especially the double overlay cameo pieces were remarkable, renewing old processes, and very difficult to make at that time particularly in double overlay never mind single overlay cameo) and beautiful?