Considering very thin capillaries, such as found in wood to transport water (~100Micron), I understand that the two main factors in play are gravity and the adhesive forces between the water and the surface of the capillary tube. I understand that gravity is proportional to volume that is (radius)^2 whereas adhesive forces are proportional to inner surface area of tube that is (radius)^1. So for some small radius adhesive forces are stronger than gravitational pull. However it seems as if this is independent of length. It seems that since both gravitational pull and adhesive forces, being proportional to volume and surface area, are directly proportional to some ΔL, then the length of the tube is irrelevant and the water will climb up until the tube ends. However, we still define a certain capillary length for capillaries. Does this capillary length exist for very thin capillaries? Or would water climb indefinitely in a very thin perfect tube? And if it does exist why would it depend on length anyway? Thanks.