Iron metal is not easily ground or crushed.
The flow of four different liquids from four pipets is started simultaneously to test their viscosity.
Four funnels are connected to differing lengths of capillary tubing. The greater the length of the capillary tube, the longer it takes for the water to flow through the apparatus.
This is an introductory movie showing, in wider angle, the manner in which the experiment for measuring relative viscosity is performed.