You may come across all sorts of odd things if you wander off the beaten track in the hills. This is a brass rain gauge, twin walled like a flask to insulate and reduce evaporation. This and another similar I’ve come across in the Wicklow Gap area of Co.Wicklow. It would have been a job for a local to visit this gauge on a daily or weekly basis and measure the amount of rainfall between visits. Met Éireann would have employed such people in the past though I’m fairly sure that all such measurements of precipitation, pressure and temperature etc are made by automatic weather stations now.