October on this Island has a rhythm to it, and this year that rhythm runs through our historical buildings. On Oct. 10 and 11, from 10 am to 4 pm, the Grange Hall in West Tisbury fills up with tables of handmade goods for the Vineyard Artisans Fall Festival. On the 25th, the Agricultural Hall fills up, but this time it’s with pie contests and sustainability demos, for the Ag Society’s sixth annual Harvest Festival. Two weeks apart, two historica…