Aged 35 in 1841 (looks a bit like 25) with Eliza, also 35
Aged 46 in 1851.

10 APR 1805   Moor Lane Baptist-Formerly Scotch Presbyterian, Bolton Le Moors, Lancashire, England.  This Church was only founded in 1803, so Parents John and Mary may have been married here, or another Baptist Church.

Name:    Cornelius Buckley
Birth Date:    10 Apr 1803
Birth Place:    Bolton, Lancashire, England
Event Type:    Birth
Father:    John Buckley
Mother:    Mary Buckley
Denomination:    Baptist
Piece Title:    Piece 1022: Bolton, Moor Lane (Baptist formerly Scotch Presbyterian), 1793-1836
and
Name    Cornelius Buckley
Birth Date    10 Apr 1805
Birth Place    Moor Lane Baptist-Formerly Scotch Presbyterian, Bolton Le Moors, Lancashire, England
Father    John Buckley
Mother    Mary
FHL Film Number    0560877 (RG4 1022)

BUCKLEY  Cornelius  68  Bolton  8c 249

Lancashire Death indexes for the years: 1873
BUCKLEY    Cornelius    68    Lever    LEV/11/447

BUCKLEY, Cornelius
buried on: 06 June 1873
recorded at:   St Stephen, Lever Bridge (Lancashire)
date of death   06 June 1873

Bolton Weekley Journel, Sat 14 June 1873:
Drowned after "enjoying himself on Friday Night until a late hour" fell into some water while trying to climb over the back yard wall.

Cornelius is buried at St.Stepeh, Lever Bridge.  There is a headstone (see pictures).  Cornelius (68) is buried with wife Esther (66), sons Josuah (5) and Ephraim (9 mo) and daughter Sarah Ellen (61).

Just a guess at the age, based on Cornelius's

Died before Q3 1837 (as no younge deaths on GRO except Saddleworth in 1838, aged 26 or 42).  Two possible burials (no ages):

Name    Margaret Buckley
Death Date    Jan 1836
Cemetery    New Jerusalem Temple Cemetery
Burial or Cremation Place    Salford, Metropolitan Borough of Salford, Greater Manchester, England
Has Bio?    N
URL    https://www.findagrave.com/memorial/245420761/margaret-buckley


Name    Margaret Miller
Death Age    31
Birth Date    abt 1806
Burial Date    29 Aug 1837
Burial Place    Brindle, Lancashire, England
Register Type    Parish Register
Reference Number    PR 92
Brindle is between Chorley and Preston.  Age is a good match, so perhaps Margaret was from here.

Birth:  24 MAY 1827   Moor Lane Baptist-Formerly Scotch Presbyterian

Aged 15 in 1841 (at Crook Street)
Aged 24 in 1851, born Ashton
Aged 44 in 1871, born Lancashire Lees

Name:    James Buckley
Gender:    Male
Birth Date:    24 May 1827
Birth Place:    Moor Lane Baptist-Formerly Scotch Presbyterian,Bolton Le Moors,Lancashire,England
Father:    Cornelias Buckley
Mother:    Margret
FHL Film Number:    0560877 (RG4 1022)

James may have been born at Ashton (1851 census)
 

James died after 1901, most probably 1895 (only Oldam Town death record) or 1899 (registered at Delph, Oldham).

The James Buckley that died 25 Mar 1897 and buried at Crompton Cemetery is another (married toi Maary).

Lancashire Death indexes for the years: 1895
BUCKLEY James    69    Oldham Below Town    OBT/152/83

Name    James Buckley
Age    69
Estimated Birth Year    1826
Registration Quarter    Oct-Nov-Dec
Death Registration Place    Oldham, Lancashire, United Kingdom
Death Date    Dec 1895
Inferred Death Place    Lancashire, United Kingdom
Volume    8d
Page    489

Aged 7 in 1841, born Bolton
Aged 17 in 1851, born Bolton
Aged 26, border in 1861, born Bolton
"William M" Aged 37 in 1871, born Bolton (and married to Mary).
Wm Buckley aged 46 in 1881
Aged 56 in 1891

Name:    William Buckley
Event Type:    Birth
Birth Date:    28 Mar 1834 (Should be 8th, not 28th)
Birth Place:    Bolton, Lancashire, England
Denomination:    Baptist
Father:    Cornelius Buckley
Mother:    Margt Buckley

Name    William Buckley
Age    71
Estimated Birth Year    1833
Registration Quarter    Jan-Feb-Mar
Death Registration Place    Bolton, Lancashire, United Kingdom
Death Date    Mar 1904
Inferred Death Place    Lancashire, United Kingdom
Volume    8c
Page    307

Lancashire Death indexes for the years: 1904
BUCKLEY    William    71    1904    Horwich, Bolton    HOR/27/46

Cant be this grave, as death registered Q1/1904, but there is no death registered in Q2/1904, so maybe it is:
BIRTH    unknown
DEATH    11 May 1904
BURIAL    Philips Park Cemetery
Miles Platting, Metropolitan Borough of Manchester, Greater Manchester, England
PLOT    FRoman Catholic 476
MEMORIAL ID    140911806
(Only person in plot 476)