My wife is an Ackerman and we are researching her family history. I saw your message and looked in the Public Records here in England for a George and Robert A Ackerman in Somerset. I'm afraid I couldn't find either of them. The only George whose birth is registered in England in 1847 was a George Edward Akerman(different spelling) whose birth was registered at Cirencester, Gloucestershire.That's the next county to Somerset. The best match for Somerset is a George Henry Akerman whoses birth was registered at Chard in 1848. Robert A Ackerman is a blank. There is no registration in 1856, 1857 or 1858. How good is your information? Is it based on family legends or is it more concrete. Let me know, I may be able to help. Living on this side of the pond, I am a bit nearer.