There is a memorial at the Eastern Cemetery in Edinburgh and although the picture available on the web is not that clear, the names are arranged in date of death order.   There appears to be a Jackson of the 1st Bat.Welch Regiment in 1923
Last name   Jackson
Age   40
Birth year   1872
Birth town   Edinburgh
Birth county   Midlothian
Birth country   Scotland
Service number   3850
Regiment   Welsh Regiment
Unit / Battalion   1st Battalion
Year   1912
Residence town   Edinburgh
Residence county   Midlothian
Residence country   Scotland
Series   WO 363
Series description   Wo 363 - First World War Service Records 'Burnt Documents'
Archive   
The National Archives
Record set   British Army Service Records
Category   Military, armed forces & conflict
Subcategory   First World War
Collections from   Great Britain, UK None
There was an illegitimate birth 13 February 1871 to Catherine Jackson, Domestic Servant, of a James Campbell Jackson.    No father named,  as was the case on the death certificate.