Hi Hume 24
thanks for that info. about the IGI.

I have used it a few times but it was ages ago and I had no success at all. I don't think it works too well for Irish Ancestry. I'll remember it next time I'm looking though.
In answer to your question, yes I am taking the 27 year old as my Mary. This age still fits in with her age for the 1861. The other Mary is too old at 35. Obviously the address is a match too.
Now, regarding the children of Mary Russell. Does anyone have an opinion regarding a father. I was quite happy to see the first child, James Irving Russell to have his dad's first name and Irving used as an approximation of his surname. To see two other children with the names Lynch and Owen as middle names is confusing and, to be honest, quite shocking if they have different fathers. It may be possible that the name Irwen has been misheard as Owen for Robert but I can't understand Lynch.
Looking at the 1851 census there is a family of Russells living in the Gorbals with a Mary and sister Margaret that appear to be the same family. There are a couple of other families but they don't meet the criteria of Glasgow births for the two girls.
In 1861 there are a few possibilities for both girls living separately but none together, as far as I can see.
In 1871 there are a couple of James Irvines living in lodgings but none that I can find as an Iron Puddler. The rest of his family from 1861 seem to have disappeared by 1871 too.
Thanks again for the IGI info. and for Catherine's details.

I'll have another search later today and keep you posted.

Tony