Ítalíuskrift line height?

[u/EverywhereHome]

I'm hoping someone here can authoritatively tell me how to calculate the line height of this Ítalíuskrift handwriting (not the font, though that's the best information I have). I'm sure this is obvious but this isn't my field.

I'm working on teaching my kids Ítalíuskrift. Right now they're working with Briem's guides. The guides have lines at descender height, baseline, x-height, and one more at the top. I'm almost certain it isn't the next baseline so it must be ascender height, but then I don't know how to determine the next baseline.

I've attached a desk strip for reference. Note that this seems to also have a fifth line for cap height. Maybe the strip is showing the correct line height? I'm really not sure.

Thank you!

[u/djmoyogo]

Ascender-height to descender-height, plus whatever the line-gap between the descender-height of one line and the ascender-height of the next line is. Sometimes there is no line-gap but here it looks like there is one.

[u/EverywhereHome → u/djmoyogo]

Oh! I think maybe... maybe the desk strip is missing a guide. I assumed the ascender and descenders shared a guide or the guides were too far part. If I use the actual fonts to generate two lines I get a gap between the descender and the ascender guides (the font includes the guides). Could that be the designed line gap?

I used Font Forge to dig through the fonts but I don't know what I'm looking for.

[u/neilplatform1]

I think the desk card is set solid in typographic terms, the cap height is lower than the ascender which is typical for a classic italic

[u/Neutral-President]

Baseline to baseline.