I think I have finally traced my gg-grandmother to Perthshire. Her name was Jessie McBeath (sometimes spelt Macbeth), the daughter of Alexander McBeath and Janet Stewart. The children of this couple were all christened in Blair Atholl. Jessie was born in 1843 but by 1863/4 she was in London, and by 1873 she was in Lancashire married to or living with Richard Noble Parkinson.
I also have the will of an Alexander McBeath who was married to Marjory, aka May, MacGregor who lived in Blair Atholl and Moulin. I'm not sure if/how these two families are connected. If anyone recognises these names or could help establish a link, I would love to hear from you.