Lots of individual records are linked to letters, newspaper articles, etc. through the soldierlinks table.
For e.g. Dick Irvin <http://canadiangreatwarproject.com/searches/soldierDetail.asp?ID=70961> is linked to this letter <http://canadiangreatwarproject.com/transcripts/transcriptDisplay.asp?Type=L&Id=229>. The transcripts are found in the generaltext table.

The logic seems to be: when loading an individual's record, look in the soldierlinks table for the soldierID and retrieve the linkIDs associated with it. Go get that linkID from the transcriptions table, which contains components for the HTML output. When users click the link (in the linkAuthor field) they see the letter or w.h.y., from the generaltext table. The generaltext table entries have an indexVal field which conforms to the overall letter. This may be made up of n entries (as below) in the generaltext table.

The letter (above) is actually three entries (delimited by the horizontal rule in the HTML output). The first is entryType LTRP, which I take to be a preamble. The second bit is an entryType LTRM, which I will call the main letter. The last bit is an LTRS entryType (SIC, maybe?) which appears to be a correction of portions of the letter.

The soldierlinks table has several link types: LTR (letter), WD (war diary), and NWS (newspaper).