Can I control or limit the number of lines appearing in a field where I have turned on ""log edits to this field""?

Limit lines "appearing" in the field or "entered" in the field? If the question is just on the appearance (in other words, display), I think you have control on it by putting a number underneath the "display" option (number of lines, max characters, and width of input box). I don't know the answer if you want a limit on how many lines a user can enter in the box. Hope it helps.

I'm actually talked about the "log entries" box.   I'm logging changes to at text field.  Each time the value of the field changes, the system adds a line to the field.  I don't want to show more than 4 or 5 lines.

Hmmm ... Yes, by default, it puts a white space in between each edits in the log field

Kathy, yes, you can make a formula field to show just the more recent updates.  That would show in view mode.  I that what you want.

But my better suggestion is to use some formula i can provide which will parse out the most recent value, and who and when it was done.  Then if the user need to see"who done it when" they can edit the record, which will then allow access to the full history of the changes.

Is that what you really want?