but not under the prefixes—
D as Abbadie not D'Abbadie Da " Silva " Da Silva De " La Place " De La Place Von " Humboldt " Von Humboldt Van " Beneden " Van Beneden.
| D | as | Abbadie | not | D'Abbadie |
| Da | " | Silva | " | Da Silva |
| De | " | La Place | " | De La Place |
| Von | " | Humboldt | " | Von Humboldt |
| Van | " | Beneden | " | Van Beneden. |
It is an acknowledged principle that when the prefix is a preposition it is to be rejected; but when an article, it is to be retained. When, however, as in the case of the French Du, Des, the two are joined, it is necessary to retain the preposition. This also applies to the case of the Italian Della, which is often rejected by cataloguers. English names are, however, to be arranged under the prefixes:
De De Quincey Dela as Delabeche Van Van Mildert,
| De | De Quincey | |
| Dela | as | Delabeche |
| Van | Van Mildert, |
because these prefixes are meaningless in English, and form an integral part of the name.
Whatever rule is adopted, some difficulty will be found in carrying it out: for instance, if we consider Van Dyck as a foreigner, his name will appear as Dyck (Van); but if as an Englishman, his name will be treated as Vandyck.
A prefix which is translated into the relative term in a foreign language cannot be considered as a fixed portion of the name. Thus Alexander von Humboldt, when away from his native Germany, translated his name into Alexandre de Humboldt. The reason why prefixes are retained in English names is because they have no meaning in themselves, and cannot be translated. There is a difficulty here in respect to certain names with De before them; for instance, the Rothschilds call themselves De Rothschild, but when the head of the family in England was made a peer of the United Kingdom he became Lord Rothschild without the De. In fact, we have to come to the conclusion that when men think of making changes in their names they pay very little attention to the difficulties they are forging for the cataloguer and the indexer.
In this rule no mention is made of such out-of-the-way forms as Im Thurn and Ten Brink. It is very difficult to decide upon the alphabetical position of these names. If the indexer had to deal with a number of these curious prefixes, it would probably be well to ignore them; but when in the case of an English index they rarely occur, it will probably be better to put Im Thurn under I and Ten Brink under T.