From this list as first printed we have dropped 190 titles some because they were out of print or not easily obtainable; some of the more recent books because their popularity has passed; some of the older ones because they were found to be very rarely read; and some because for one or another reason they are thought not worthy of a place among a thousand of the best. We have added other books to replace those dropped, choosing them for reasons set forth in the original introduction which follows.