A bunch of Syriac works on scientific subjects are preserved in a single manuscript in the BNF in Paris. Most are by Severus Sebokht, the 6th century monk and bishop at the monastery of Kinnesrin, where Greek studies thrived.
I have a microfilm of this manuscript, and it contains a number of letters by Severus. One of these is of wide interest; it defends Syriac science against the Greeks, and incidentally mentions (for the first time) the numbers that we today call “Arabic” numbers. But it has never been translated; all our knowledge of it is from a small excerpt.
This is a reminder to myself; I need to get this transcribed and translated and put online! That’s why I got the microfilm!