Roman Musical instruments..

[M. Demetrius]

Thanks, Susanna
I have two more questions for starters, if you please

1 In the picture from your link, I'm guessing the type of wood isn't that important, except that it needs to be strong enough to keep from bending under the stress of the strings. What approximate dimensions can I use for reference?
2. Are the strings plucked like a harp, or struck like a hammered dulcimer? I'm supposing the instrument tied to the sound board is the plectrum, or the hammer, am I right?

Thanks again.