Enhancements made: the indices

In order to make the digital edition as useful as possible, I have added this preface, a full table of contents, and two indices.

The first index (starting on [page 477]) is an index of topics discussed. It is a selective rather than an exhaustive index for the following two reasons:

(1) A commentary is already in effect indexed by the text it is linked to. If, for instance, readers wish to find what the commentary has to say about a certain passage, all they need do is turn to the part of the commentary dealing with that passage.

(2) A digital edition can be searched online very quickly and easily. A reader wishing to find any mention of the eminent Dutch textual critic Nicolaus Heinsius could find every mention of Heinsius in the edition simply by using "Heinsius" as a search argument.

However, some of the discussions in the commentary do not have an obvious link to the text, nor would they necessarily be found quickly by an electronic search. An example would be the discussion of "Simple verbs used for compound ones" at [page 281].

Also, there were some parts of the introduction and commentary which I wanted to highlight to the reader as being of possible interest: including references to these in the index would serve this purpose.

For similar reasons, I have included (starting on [page 489]) an index of textual emendations first proposed in this edition. Some of these emendations involve works other than Ex Ponto IV, and authors other than Ovid. The index of textual emendations makes these corrections easy to find.