-?)
So I'm to understand that Maria Beale possibly had three children by a guy also with a surname Hamblen, and it appears he could have been a wine merchant, called Jacob Henry Hamblen?
He is named as Henry Hamblen (says Hambler) on the birth certificate of the first child, but I think he could be Jacob Henry, yes.
So with three children Maria Beale, used the surname of the assumed father Hamblen.
Might there have been a possible marriage to Mr J. H. Hamblen?
No, she was a spinster when she married Mr. Collins later (despite using the Hamblen name)
Jacob Henry Hamblen was already married to Julia. I think they may have split up, but can't be sure at the moment.
We then learn that Maria Hamblen (nee Beale not used) married a Samuel Collins.
Date/Year known?
Samuel and Maria married 21 April 1877, and I posted the image in Reply #134
Henry Hamblin Hamblen or Hambler, what ever his surname was, its appears to be a bit of a nightmare to establish what actually was the original surname and that perhaps the spelling has varied over the years due to registrars errors.
I believe original certificates or digital images are needed to check all these entries to see where the variations began.
Interesting to see Henry Hambler (1828-1874) and Maria E. Beale (1849-?) had a 21 year age gap!
If i'm correct we know the dates of this Henry having passed away aged 46.
But for Maria E. Beale we only have her birth year 1949.
She married Samuel Collins in 1877 aged 28, 3 years after the death of her first partner/husband, Henry.