There is also a copy at the Bibliothèque nationale de France, however, and it has recently been made available online via Gallica:
The availability online of this previously rather inaccessible catalogue allows us to understand the Brölemann collection, and the annotations in its manuscripts, more easily than before.
First, this catalogue explains the numbers preceded by "A" or "B" that occurs on the blue-edged labels: the catalogue printed in 1897 refers to a "catalogue A" and a "catalogue B", whose numbers correspond to the labels. These were therefore presumably two older handwritten catalogues or inventories, superseded by the printed one.
Using two of the images above as an example, we see that one manuscript (Vol.II of the Bible of Louis de Harcourt) described as no.17 on p.8 [and 9] of the printed catalogue, was no.147 in Catalogue A, and no.106 in catalogue B:
In due course I intend to tabulate the numbers of the three catalogues to see what patterns emerge. It is apparent, for example, that the printed catalogue arranges the manuscripts in chronological order; no.1, for example, a 10th-century Evangeliary, bought at the Didier-Petit sale in 1843, was no.135 in catalogue A, and no.60 in Catalogue B. It would be very interesting if one of the two earlier catalogues records the manuscripts in order of their acquisition.
Sometimes someone (Arthur?) has added references to the older catalogues to the bookplate:
And in one case a label with a B number superseding an A number:
If enough examples could be collected it ought also to be possible to decipher the Brölemann price-code. From the images above it is apparent that "x"=0, and other numbers are represented by "d", "t", "l", "q", "u", "s", "c" and/or "e". I encourage readers to send me any examples they encounter.
Edit 25 March 2015
I have added a few more images above, thanks to Don Skemer at Princeton.
Edit 16 February 2016
I have added a few more images above.
Edit 8 May 2016
I have found a note in my copy of Christie's, 29 November 2000, alongside lot 21, that there was a note on the back pastedown headed "B.48", and at the front the catalogue numbers "B.48" and "C.68", a note "Catalogue inprimé page 33 no.68", and the usual blue-edged label inscribed "A.216 | dcx[?]".