For diameter-size of the precision (giant) optics required for both astronomy and electromagnetic energy-handling, there is no substitute. However, the cost of "difiractionlimited" (or geometrically optically unimprovable for given wavelength-and-diameter [1]) optics on Earth, goes up by the fourth power of the diameter [2,3], In the visible-band diffraction-limited case, for example, this is due to difficulty of grinding a given solid surface to a "Rayleigh Limit" or V4 (or 5 x 10"^ in. for green light) maximum tolerance overall while polishing it sufficiently to exhibit a uniform "Beilby" layer or surface consisting of an irregular collection of small peaks or pits none of them more than a molecule or two in height or depth [4,5], In the formation of such smooth, polished, "Beilby" layers on solids in the process of optical finishing, we have results corresponding to the smoothing out of liquid surface irregularities under "surface tension." FIGURE 1 R.W. Wood’s Mercury Mirror Telescope The feasibility of using liquid-surfaced optical construction principles for astronomical quality mirrors was first demonstrated by R. W. Wood in 1908. Using a vertical axis, spinning (therefore dynamic paraboloidal), 20 inch diameter dish of mercury, Dr. Wood resolved 5 arc second double stars near the zenith with a hand held magnifier. Capillary Properties of Liquids Meniscus properties of liquids long have been known in physical chemistry and surface chemistry. For example (Figure 2), the well known Dupre-Young equation establishes the relationship among solid-vapor, solid-liquid and liquid-vapor contact angles for a clean liquid in contact with a clean, flat solid. Hysteresis of contact angles (Figure 3)
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