Abstract:
CAPILLARY MOVEMENT OF MOISTURE IN GRAVELS AND SILTS, AND ALSO IN COMBINED SYSTEMS (SILT-SAND AND SILT-SCREENINGS) IS DESCRIBED IN THIS PAPER. THE EXPERIMENTS WERE PERFORMED IN LARGE LUCITE TUBES, 5 5/8 IN. AND 3 5/8 IN. IN DIAMETER AND 4 FT HIGH. THE SHAPE OF THE TIME CURVES OBTAINED BY PLOTTING THE HEIGHT OF THE VISIBLE MOISTURE BOUNDARY AGAINST TIME WAS PARABOLIC OF VARIABLE ORDER. BY PLOTTING THE ACCUMULATED VOLUME OF MOISTURE LIFTED BY THE SOIL AGAINST TIME, DISCHARGE CURVES FOR A PART OF THE EXPERIMENTS WERE TRACED AND THEIR SHAPE COMPARED WITH THAT OF THE TIME CURVES. THE MOISTURE CONTENT ALONG THE HEIGHT OF AN EXPERIMENTAL TUBE GENERALLY DECREASED FROM THE BOTTOM TOWARDS THE TOP, BEING, HOWEVER, PRACTICALLY UNIFORM IN SOME PARTICULAR CASES. ATTEMPTS TO UNDERSTAND THE MECHANICS OF CAPILLARY FLOW WERE MADE BY INTERRUPTING THE CAPILLARY PROCESS AT DIFFERENT HEIGHTS OF CAPILLARY RISE AND MEASURING THE CORRESPONDING MOISTURE CONTENTS. IT WAS CONCLUDED FROM THE STUDY OF MOISTURE DISTRIBUTION AND FROM OBSERVATIONS OF CONDENSATION PHENOMENA INSIDE THE TUBES, THAT THE MOVING CAPILLARY MOISTURE IS PRECEDED AND ACCOMPANIED BY WATER VAPOR. THE CONCLUSIONS FORMULATED IN THIS PAPER MUST BE CONSIDERED AS SPECIFICALLY PERTINENT ONLY TO DESCRIBED CONDITIONS, AND FURTHER RESEARCH DATA ALONG THESE LINES ARE NEEDED. /AUTHOR/
Supplemental Notes:
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