It is like an upside down test tube, but has a groove leading to a hole at the side of the curved top. I need to work out the best way to make the wooden holder over the test tube and have a hole in line with the hole in the test tube. I know I can make this, I was just being lazy and looking for ideas on design.
Maybe I will just continue using the design similar to the one linked by Grahamshed which I have made before. I was ordering some other stuff from Turners Retreat and thought the dispenser looked interesting.