| Rhif Cyf Amg | RHIW/3 |
| Teitl | Large broad-sheets, not printed upon but written and ruled by hand in pencil, giving particulars of slate-making |
| Disgrifiad | The two right end columns give the total cost of production for the various working "companies" and the "value of production". The figures in red ink are significant. |
| Dyddiad | August 1899-December 1899 |