Drych yr Amseroedd: yn cynnwys ychydig o hanesiaeth am y pethau mwyaf nodedig a ddigwyddasant yn bennaf y'Ngwynedd, yn y ddwy ganrif ddiweddaf, mewn perthynas i grefydd ... : mewn dull o ymddiddan rhwng Ymofyn-gar a Sylwedydd

Robert Jones is known as the historian of the Methodist revival in Wales. ‘Drych yr Amseroedd’ is considered his best work; his masterpiece. It is a comprehensive account of the Methodist revival in Wales and was compiled mostly through individual interaction, between the author, Methodist leaders and members. Jones himself was a Calvinist Methodist preacher and had personal and familial connections with key revival figures, such as Howell Harris.