Barzilla/Barzillai Silkwood and his brother Solomon are listed as having come from England as you can see at tinyurl.com/kafzhf9. The surname probably comes from a place so named such as Silk Wood in Gloucestershire or Silkwood Top in Devon.
Barzillai is a biblical name as you can see at
http://en.wikipedia.org/wiki/Barzillai#Barzillai. It means 'of iron' in Hebrew.