Greetings,
Are you sure on this John Blake being born in Sandwich?
I checked my Vital Records of Sandwich Mass to 1885, Kardell and Lovell, and find no record of him there.
I have Blakes in my past and I have him as being born in Dorchester Mass around 1640. I have quite a bit of Blake lines in my work and I post all my sources also so feel free to check out
www.allaboutnhre.com/familytree This John Blake is probably my weakest member of this line so if you find more sources/facts please share them if you could.
I noticed I do not have any source info for the "Dorchester" conclusion which means I must have seen that on a OneWorldtree or Rootsweb site or some other personal website that did not list the source. I don't trust those sites enough to reference them as sources but lacking anything else I'll put the info in my tree as a "clue" that needs to be chased down. As I said I have my other Blake stuff pretty well documented and I hope it helps you cousin:)
Best regards,