Dros y blynyddoedd, mae stafelloedd Plas Tan y Bwlch - canolfan Parc Cenedlaethol Eryri ym Maentwrog - wedi cynnal llu o sgyrsiau a darlithoedd sydd wedi codi hwyl a difyrru. Yn y gyfrol hon ceir casgliad o dair sgwrs am gymeriadau'r chwareli, ffraethineb Bro Hiraethog ac atgofion dyn ambiwlans gan Emrys Evans, Gwilym Morris a John Hughes, mewn sgyrsiau a recordiwyd gan Twm Elias = A collection of three humorous talks on the subjects of slate-quarry characters, Bro Hiraethog wit and reminiscences of an ambulanceman presented by Emrys Evans, Gwilym Morris and John Hughes, talks recorded by Twm Elias at courses held at the Snowdonia National Park Centre at Plas Tan y Bwlch, Maentwrog.