Painted by an unknown artist and hanging in the Blake Museum in Bridgwater. I’ve not been able to find out much about William apart from the dates of his birth and death (1635-1707) which date this portrait to 1649.
It’s quite a dark somber picture, but you can see some details here: the tassels on his band strings and the buttons on his doublet, fashionably open to display the linen of his shirt (which is also visible through the slashes on his sleeves). Tricky to spot any more detail, but there may just be a wide band of lace on his falling band and possibly some red-worked embroidery on the lining of his right hand sleeve.
The 1640s Picturebook 