Metal identity plate for owners of horse drawn carts

"This type of identity plate was required by the British government to be affixed to the shafts of all horse drawn vehicles. P.H. Pearse defended the user of one such cart who did not have plate displayed. This, as far as I know, was Pearse's only law case. He represented the defence. Case made famous in a song called "An Trucaillín Donn". Measures approx. ten and a half inches by three and a half inches. Belonged to my grandfather, Richard Comerford, who lived in Garryduff, Grangemockler, Co. Tipperary. Rescued from a scrapheap."