I'm having a root through the records to see what I can find for you. You may well indeed have all of this information already, but just in case not here goes (sometimes tid-bits can be of help)
I've not been able to find Alfred Meech at all after the 1861 Census when he's living in Jersey with his Grandmother Anna (Hannah) Meech and his sister Sarah Ann.
*I wonder when Anna (Hannah) Meech moved over from Dorset to Jersey? I've not been able to find her on the 1841 or 1851 Censuses.
I thought I'd then look further back and around for you.
The marriage of Samuel Meech and Hannah Wakely (or Makely) Hine takes place on 13/6/1824 in Burton Bradstock Dorset
I found the Baptism of William Hine Meech on 10/7/1825 in Burton Bradstock Dorset, son of Samuel and Hannah Meech. Samuel Meech an Ag Labourer.
There was a sister Baptised on 23/9/1827 in Burton Bradstock Dorset, named Martha Meech, daughter of Samuel and Hannah Meech.
I have not managed to trace Samuel or wife Hannah on the 1841 Census.
I found a burial record for a Samuel Meech on 14/4/1844 in Burton Bradstock. Year of birth 1796 aged 48.
Moving on to the children of William Hine Meech.
I found the Baptism of Sarah Ann Meech on 23/6/1850 in the Parish of Melcombe Regis, Weymouth Dorset, parents William and Mary Meech. Father a Wheelwright.
There was also the Baptism of Sarah's twin brother Alfred Meech 23/6/1850 (same parents and details).
He must have died not long after his baptism, as his death record appears on Free BMD in Q3 1850 Weymouth Dorset.
I wondered at first if it was William Meech on the 1851 Census in Portsmouth Hampshire, he is listed as being 36 and born in 1815 Bridport Dorset His occupation is given as Smith HM Dockyards and his status as married, but this William appears on the 1861 Census also with his wife Jane and two daughters. He is a smith at the time of this Census also.
So no sighting of William anywhere on the 1851 Census, or the 1861 Census or beyond.
PS I've just found your other rootschat postings stating that Alfred may have changed his name from Meech to Williams.
There is an Alfred Williams on the 1911 Census, he is single, was born in Jersey and is living in Southampton Hamsphire. Date of birth 1856 (two years out), but you never know.
Links to other rootschat posts to help collate information
http://www.rootschat.com/forum/index.php/topic,552406.0.htmlhttp://www.rootschat.com/forum/index.php/topic,552404.0.html