They certainly look interesting Alan, given that he appears to be a contemporary of Beethoven. However, it would seem that, if they date from around 1790, that would make them contemporaneous with the later symphonies of Haydn and Mozart. In my experience, so far, none of the other symphonies I have heard written at that time seem to anywhere near come up to the standard of these two masters, that is, apart from a few of those written by Haydn's kid brother Michael.
However, I'm always ready to be proved wrong!
