While still a teenager, in May 1853, he travelled to Liverpool, walking to Tregaron and then for 40 miles (64 km) to Llanidloes via Pontrhydfendigaid, Devil's Bridge and Plynlimon, before completing his journey by canal boat and train.

[5] Before his death, Thomas selected 3,113 glass plate negatives which were bought by the educationalist and historian Owen Morgan Edwards to illustrate his Welsh language magazine Cymru.

In an age when the portraiture was dominated by respectability, he chose to photograph ordinary people, with some of his less conventional portraits showing beggars, drunkards and vagrants.

[8] A memorial card, made from the portrait of Reverend John Phillips, was particularly popular and Thomas noted that over a thousand prints of this negative were sold in the six weeks following the death of the minister in 1867.

He attended the General Assembly of Welsh Calvinistic Methodists, where he portrayed the ministers gathered on a plot of land used for growing potatoes behind a chapel in Llanidloes.

During this tour he also visited his home at Lampeter, where he took a photograph of his mother, Jane Thomas, sitting between two other women all in traditional Welsh dresses.

In 1868 he made the journey to Wales again, this time attending the Eisteddfod festival at Ruthin Castle, and took a group portrait of the literary and musical stars.