I'm puzzled. I have a pretty little Vivace from a violin concerto by Paolo Tommaso Alberghi (see IMSLP; he seems to be one of those many baroque composers who wrote a lot, of which most was lost, and what little remains is represented by a single document in IMSLP - which we're lucky to have at all - many thanks, whoever scanned it).
The time signature is 3/8. The first bar is no problem: 4 beamed semiquavers and a quaver.
Bar 2 has two semiquavers written a little less heavily than the rest, followed by 3 beamed quavers. I can't think of any way to play this except as a triplet in the first quaver's time, followed by two normal quavers (to my ears this sounds quite nice, but I have no idea whether it's what Alberghi intended!).
Bar 5 is the first of a series which of bars that all consist of three tied and beamed semiquavers followed by two beamed quavers. I am assuming the three semiquavers are intended to be played as a triplet? Is the tie merely an indication that they're a triplet, or does it intend slurring too? I'm playing (incorrectly) in a recorder instead of violin, so I'm on thinnish ice anyway.
The grace-notes bother me. I really don't know what they mean. I'm assuming the three notes must be played in the time of the first quaver as I can't see where else they could steal time from. If so, I don't know whether to let the first grace note take longer, like an arpeggiata (which it could - it gives the melody a little lilt, which feels a tiny bit like French inequality), or whether to play them more evenly, which the way I'm doing it, places the emphasis on the main note.
Any help greatly appreciated.