The Irish in Scotland

When I was researching my father side of the family, from the 1851 Census of Canada. I knew two things, That William Bonner was born in Scotland and his wife Jane Holmes was born in Ireland. At that time, I didn't know where or when they met or what date they got married. William Bonner and Jane Holmes are my 5 generations great grand parents. I contract a relative, who was also doing family research and she gave me some information, when William Bonner and Jane Holmes got married. August 16, 1841 in Dundee, Scotland. My first question, was how did Jane Holmes end up in Dundee, when she was born in Ireland. After some researching I found out that for centuries that Irish and Scottish people have been emigrating to each other countries. In the 1830's and 1840's, there was a sharp decline of the textile industries in Ireland. At the same time a huge demand for textile workers in the Dundee area. The introduction of jute which was cheaper than flax, resulted in a mass immigration of Irish people to Dundee Scotland. I found Jane Holmes in the 1841 Scotland Census, with her parents John and Rebecca and her brothers and sisters. Which I didn't know she had. The census shown that,they were were born in Ireland and their occupation was Linen Handloom weaver and winder and they lived on Rose Street. So, they work in a textile factory. I also, found William Bonner, who lived not to far on James Street and also was a Linen Handloom weaver. I believe they work in the same factory. They lived in Dundee for 5 years, and had five children. Three didn't survive their first birthday. I believe the rapid urban expansion of Dundee and the industrial revolution made cities a very bad place to live. In 1846, they emigrate to Canada.