A glass tube of 0.0736‐inch or approximately two‐mm bore was placed in a nearly horizontal position with one end slightly bent and immersed in a glass jar filled with water, as shown on Figure 1. For a given inclination of the tube the water flowed up the tube to such a distance from the outlet that the height of the capillary meniscus in the tube above the water‐level in the jar was equal to the vertical height of capillary rise, in accordance with JURIN'S law.