In the interest of being fair and giving reasons for my comments on this thread, and to demonstrate my reservations over using the Cyril Manley book as a reference source, I have looked at some of the pieces in the book on a 'flicking through' basis rather than a 'deep research on each item' basis, and these are my thoughts.
The items I mention below are not exhaustive. They are just the pieces where I recall having seen id queries raised on over the years. There are other pieces where for me, my gut instincts would query their identification enough to ensure I researched further, and also
I don't recognise many of the items in the book so obviously cannot know whether they are correctly identified by him. This is not helped by the fact that his photographs were taken against a black background making identifying features nearly impossible to see on some of them.
So I believe I recall there being reservations over the following items -
numbers 16, 17, 18, 19, 20 - where they have been id'd as Richardson's and where I think they have been subsequently id'd as Kralik
(Plus 14,15 where they may not be English, but possibly Bohemian imho)
35 which has been identified via a pattern drawing as Harrach iirc
57 which has been identified as Loetz iirc
63- This has been id'd in the book as Richardson but I think there is a query over this being either Bohemian or French possibly
101 - my question - I saw this up for sale at auction but have not been able to confirm this is definitely Stevens and Williams?
102 - my question - is this really a Frederick Carder piece? I would have thought it was Bohemian - there are a number of yellow and white 'flagged' decor pieces believed to be from Bohemian makers but I'm not sure they have been sifted and maker id'd yet.
179 - Id'd as Thomas Webb, but I think this has been id'd as Kralik
187 Id'd as Thomas Webb but I believe this is a Stuart vase
192 - Id'd as Thomas Webb but I think this has been identified as Kralik
That is just a quick run through without doing any further research.
I haven't looked closely at the others.
So do you see the problem? There are some magnificent pieces of glass in the book, of that there is no doubt. And it is entirely probable that many are correctly identified.
But since a number of queries have been raised over time, it does make it extremely difficult to use this as a reference source in my opinion.
For British Glass references I would use Charles Hajdamach's British Glass (both volumes) and Mervyn Gulliver's Victorian Glass.
I hope this helps.
I do not know anything about pressed glass so cannot comment on whether or not there are mis-identifications in that section of his book.
I don't know who your comment above was directed to, if anyone, but I hope the above helps explain my comments

m