Violin notation advice requested

[Javier Ruiz-Alma]

Pardon my ignorance RE: string notation.

An 1800’s typeset I’m transcribing uses different fonts for what I figured were all fingering indications.

Is there a significance for the use of unique fonts for notes having both upper and lower number indications?

I wondered if the lower digit may point to string number, not finger number.

Sample image attached.

ViolinAnnotations.PNG
Description: PNG image