Intergranular Film Of Water: As shown by these relict structures, rocks may be monometa-morphic or polymetamorphic, depending on whether they have been subjected to one or more metamorphic cycle. Although metamorphism is essentially a process that takes place in solid rocks, the role of fugitive elements, especially the intergranular film of water, in hastening metamorphic reactions is becoming more and more evident.
GRASS will not grow well in waterlogged soil. Its roots need air as well as moisture. The ideal is a film of water surrounding each soil particle and air in the spaces between. It is as though you dipped a bunch of grapes in oil or molasses, lifted it out and held it to drain. Around each grape a film of the liquid clings, even after draining, but there are considerable air spaces between the individual grapes. Except in swamps and bogs where free-standing water is at (or close to) the surface, this is the condition that normally exists in the upper soil. But if you dig down deep enough you will, unless you hit bed-rock first, come to a level below which the spaces between the soil particles are filled with water. The top of this free standing water-its surface, is the water table. Holes you dig fill with water to this level.
Speedlights flash, the picture is taken, the film automatically advances, the shutter is cocked, and all is in readiness for the next child in the line. Similar cameras are available which operate with 35mm film. The smaller film cuts costs a bit but naturally the contact prints are not so appealing as those from the larger film.
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Photography
