The following is the outcome of a simple use of MARC-to-DC crosswalk, plugging in values from the Annie MARC record. Note that some of the fields need augmentation (via Dublin Core Assistant) ... to put it mildly.

DCMARCvalue
Title 245 Diary,|f1864 Mar. 10-1864 June 23
Creator 100 Reader, F. S.|q(Frank Smith),|db. 1842
Subject 600 10 Hunter, David
600 10 Sigel, Franz, |d1824-1902
650 0 Shenandoah Valley Campaign, 1864 (May-August)
651 0 United States|xHistory|yCivil War, 1861-1865|xDestruction and pillage
Description 535 1 Washington and Lee University Library. Special Collections
541 John A.R. Varner|cgift|d1881
545 Union soldier of the 5th Regiment, West Va. Cavalry, who served under Generals Sigel and Hunter
Contributor
Publisher
Date
Type
Format
Identifier
Source
Language
Relation
Coverage
Rights

Coverage is one of the items we're especially concerned with:

The extent or scope of the content of the resource.

Comment: Coverage will typically include spatial location (a place name or geographic coordinates), temporal period (a period label, date, or date range) or jurisdiction (such as a named administrative entity). Recommended best practice is to select a value from a controlled vocabulary (for example, the Thesaurus of Geographic Names) and that, where appropriate, named places or time periods be used in preference to numeric identifiers such as sets of coordinates or date ranges.

Refinements: spatial (point, box) , temporal (date and time)

I presume that these values will be added as qualifications to basic Dublin Core, though I don't yet know exactly how that's to be done. Thus, there's a bounding box that holds all of the points for the Reader Diary, and the coordinates of that should probably be the value for the Coverage in the DC record. The individual pages accessible via the ArcIMS interface might be noted as entries in the Relation field (viz. "isreferencedby") or possibly in Source ("isversionof")> Some examples:
<meta name="DC.coverage" content="US civil war era; 1861-1865">
<meta name="DC.coverage" content="Columbus, Ohio, USA; Lat: 39 57 N Long: 082 59 W">
<meta name="DC.coverage" scheme="TGN" content="Columbus (C,V)">
<meta name="DC.coverage" scheme="Box" content="northlimit=23.5; southlimit=-23.5; name=The Tropics">
<meta name="DC.coverage" scheme="W3CDTF" content="1945">
<meta name="DC.coverage" scheme="Period" content="start=1929; end=1939; name=The Great Depression">