The Entrepreneurial Society of the Rhondda Valleys 1840-1920, Power and influence in the Porth-Pontypridd region, by Richard Griffiths. Our Welsh relatives are from the Porth & Pontypridd areas. In addition, the featured subject of the book is James "Siamps" Thomas. Siamps Thomas was the ancestor of author Richard Griffiths, and the brother of Zephaniah Thomas, who married Elizabeth Hopkins of our Hopkins family.
The Welsh of Tennessee, by Eirug Davies. While at first glance this book does not have much relationship to our family, it does cover the Welsh immigrants and the coal industry in the state, including the 1890 time period when William Herbert started a coal mine on the Tennessee/Kentucky border. It also has some great information on the culture and society of the Welsh immigrants.