I was re-sorting books the other day, and thought about how many years it has been since I bought my Merck Index. I'm sure there are new entries in the more recent additions, but I do not have such a need to stay that up-to-date.
At first thought, it seemed to me that a book of this nature only adds entries, and does not remove any entries. But is this the case? Are compounds de-listed because they are bad science? Other reasons?
Iit would be great to know other details about the editorial process, as well, if relevant.