This partially effaced stamp is unusual, in that it says repaired by, rather than bound by. But who repaired this book? “REPAIRED BY DE xxxxxxHSY” or maybe “REPAIRED BY DAVID xxxxHSY”? The letters are .5mm high, and it is positioned in the bottom left corner of the front board pastedown.
retroReveal, which can sometimes aid in legibility of fragmentary marks didn’t help in this case.
Robert Milevski, author of “A Primer on Signed BIndings”, was not familiar with it. He did send a useful overall typology of binders stamps, however:
In research done in Princeton University Library about 15 years ago (before many 19th c books were transferred from the open stacks to offsite storage), my recording methods were necessarily primitive and thumbnail (because I had to get through half a million books rather quickly), lacking in detail, usually, other than a call number, binder’s name, and type of mark. When I went back to these records and books (a couple of years later after their going offsite), I ignored anything not obviously English. Some of the bindings represented by these ignored minimal records probably had some interesting stamped signatures, similar to yours. (A sad thing, however, is that in that interim, some of the books, because of condition, had been rebound, thereby losing their binder’s signature history.)
I did look at my main spreadsheet of English signed bindings (3600 records at present, with more than 1000 yet unrecorded) and found a couple categories of mark other than ‘bound by’ but nothing like your mark. These others include: 1. just the last name of the binder; 2. last name of binder and location; 3. name of binder, address and designation as binder, usually in a two or three-story stamp. Of course, there is 4., the category of ‘bound by x for y’, usually a department store. And 5., ‘bound by x, successor to y.’ And 6., name of binder with a month and year, or more fully, 7., name, address and year. And 8., there is also the rare upside down stamp, usually only the surname, probably from getting the front and rear boards mixed up. That’s all I can say.
Generally, before modern art conservation principals began to be applied to books in the mid-twentieth century, most restorations and repairs attempted to be as invisible as possible. So why try and point it out by stamping the book? And then why did someone else try to crudely scrape it away?
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Added 8 August 2016
Below is an image of the stamp Maria Fredericks mentions in the comments.
Peachey Conservation 
I would propose “REPAIRED BY DUPREZ LAHEY”. Marguerite Duprez Lahey bound and repaired many books for the Morgan Library during the first half of the 20th century and there are many examples of her stamps to be seen in the Morgan’s collection.
Excellent, fits in exactly, many thanks!
Despite Maria’s convincing suggestion, I’ll offer my take on it here. It looks to me like the letters “dance” a bit up and down, suggesting good work with handle letters, not a single-piece name stamp. And was the mark inked or blind tooled, rather than being gold tooled? Finally, what is the size of it? A bit large? These considerations made me hypothesize that it was done by an amateur binder, proud of the level of worked reached, and heterodox through inexperience. Could this have been very early work by Lahey for herself, with the mark scraped out after her skill had improved?
A slight expansion. In “LAHEY” (which is quite clear once it is pointed out; my compliments again, Maria) notice that the A is rotated slightly counterclockwise; also notice that the LA combination is just a bit wider spaced than the AH combination (look at the feet of the letters) despite the fact that LA has so much natural space that it always needs to be either snugged up or the other letters have to be spread out wider than usual. The rotation proves that the signature was done with handle letters, and the spacing shows that it was done by someone insensitive to letter spacing— presumably thorough inexperience.
Hello Tom! Thanks very much for your observations on my alleged Duprez Lahey stamp. Here’s what I can tell you about the Duprez Lahey stamps we have throughout the collection at the Morgan. The entire phrase “REPAIRED BY DUPREZ LAHEY” is cast as a single tool, in very small lettering. The whole line is less than 1″ in length so the lettering is quite tiny. We see these most often along the lower margin of the front pastedown, in black ink. I believe that the misalignment of letters you are seeing could be the result of paper distortion caused by somebody’s attempt to reduce or obliterate the impression. I am pretty convinced this is the same stamp, if Jeff can corroborate the size. I will send Jeff a photo and perhaps he can post it here.
Yes, I can post an image in the original post, and it is just a little less than 1″. Thanks.
Hi, Maria, good to hear from you. The small size of the letters is a telling point: I can’t imagine a semi-skilled beginner signing a book with handle letters that size. Which means that you are right, the distortion of the letters (and the apparent serifs on some of them) must have been caused by the attempt to erase the stamp.
Lahey began binding lessons around 1898, made her first trip to France in 1903, and made annual trips (except during wartime) from 1908 until her death in France in 1958. She worked primarily for Morgan from 1911 on. A repair job signed by her and later erased, on a book in private hands, would most likely have been done early in her career, or else on a book deaccessioned from or stolen from the PML. Jeff, could there be other marks of provenance that were also erased from this book?