m. (1) Joseph Turner, (2) James Rennie.

FreeBMD has this entry for a set of marriages at Halifax in 1849, which might, or might not, be her first marriage:

Surname First name(s) District Vol  Page
Marriages Sep 1849   (>99%)
Battye    William      Halifax  22  144   
Mackriel  Elizabeth    Halifax  22  144   
OLDFIELD  Mary         Halifax  22 144   
SMITH     Elizabeth    Halifax  22 144   
Taylor    Joseph       Halifax  22 144   
Terry     Jemima       Halifax  22 144   
Turner    Joseph       Halifax  22 144   
Wall      Thomas       Halifax  22 144

No Turner-Smith marriage can be found in the Scots records around that time.

The answer is that they were married in Columbo, Ceylon.
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In 1860 at her second marriage, she said she was 37, so born c. 1823.  At death in 1882 she was said to be 59, confirming the 1823 birth.
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In the 1871 census, they had moved to No 5 Buccleuch St and in relation to her husband James:
James Rennie was 44 and a Brewer maltster with 6men, born in Kilsyth, Stirlinshire
Eliz was 48 and born in Moffat, Dumfries
George S Turner, stepson was 16, a Chemistry student and born in Moffat Dumfries
John McK Turner, Stepson was 14, a scholar and born in Ceylon
James, son was 9, a scholar and born in Dumfries
William H Rennie, son, was 8, a scholar and born in Dumfries
Elizabeth J Rennie, dau, was 6, a scholar and born in Dumfies
plus
Mary Wll or Watt, sister-in-law, aged 33 of no occupation, born in Moffat, Dumfriesshire
Margaret Purdie, servant, unmarried, 27, a general domestic and born in Dumfries.
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Scots People has this record of her birth:

                                      Parent Names                 City/     GROS
No Date        Surname Forename      Frame No.     Sex  Parish   County     Data

1 02/10/1822 SMITH ELISABETH GEORGE SMITH/  F    MOFFAT   DUMFRIES  842/00 0050 0015
                                      ESTHER WHITE
                                        FR1120

The original sheet is titled 1/10/21822 and has these words:

Sept 8th, George Smith Surgeon in Moffat and Esther White his wife had a daughter born and she was baptised on the 2nd Oct called Elisabeth   (Ref 33)
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A note on the spelling of Elizabeth:

Her baptism record has the spelling Elisabeth.  (This was the only person so named on that page of 12 baptisms so I cannot tell whether this was peculiar to her parents or to the writer of the record.)

At the birth of her son George is is unclear whether Elizabeth was spelled with ’s’ or ‘z’.

At her marriage Elizabeth was clearly spelled with a ‘z’.

On the transcript of her husband’s will her name was always written with a ‘z’ and reportedly also signed by her with a ‘z’.

Possibly she changed the spelling or usage in adulthood.
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In 1881 there was a stepson Joseph J Turner, born in 1851 [or 1850?] in Ceylon living with them and employed as a Shipping Clerk and unmarried aged 30.

So far this is this first record found of his existence.
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