ABSTRACT
Fig. 22 shows the results of measurements. The theoretical curve depicted in the figure is the same as that in Fig. 20. Each experimental point is a plot of the measured critical height and the corresponding contact angle obtained from the photograph. Hence the experimental points would lie on the theoretical curve if the contact angles obtained by the method proposed here coincided with those from the photograph. Fig. 22 shows rough agreement between experimental points and the theoretical curve, which indicates the feasibility of measurement using the method proposed here. The disagreement with the curve may be mainly due to the difficulty of measurement of contact angles from the photograph since the meniscus attaches to a curved cone surface. The agreement indicated by Fig. 22 also shows the validity of the discussion given in the preceding section, where we analyzed the unstable wetting behavior based on Eq. (9) assumed in Section I.
