CAPILLARY MOVEMENT OF SOIL, MOISTURE. 61 



2^ inches in width and about three-eighths of an inch in thickness. 

 The wire, when placed within the soil, kept the soil particles apart 

 throughout most of the spaces occupied by the pad. Four of these 

 wire pads were inserted vertically within the wick, extending from 

 within about one-half inch of the water in the tank up through the 

 wick of the flume to the air above. These pads were placed in the 

 corners of the wick and about 1 inch from any side. The flume and 

 wick were then packed with soil and the experiments started. With 

 the flume inclined downward at an angle of 30°, and with the light 

 sandy Idaho soil, water dripped from the end of the flumes in about 

 four days and continued to drip until the experiment was discon- 

 tinued. This experiment was repeated, and in addition to the verti- 

 cal ventilating pads, two other pads were placed, one diagonally 

 across the wick and one in a horizontal position. The ends of these 

 pads butted against thQ vertical pads and were placed about 1 

 inch above the surface of the water of the tank. 



This flume gave the same results as the other flume, but a little less 

 water was taken from the tank in the case of the ventilated wicks 

 than in the wicks not ventilated. However, free water dripped from 

 the lower end of all of these flumes. In the wick having the vertical 

 and horizontal pad ventilators (so called) there was no un ventilated 

 space within the wick at a greater distance than 1-J inches from a 

 ventilator. 



In several of the flumes inclined downward, various other means of 

 ventilating the wick were tried and in each case free water was still 

 given off at the lower end of the flume. 



A flume inclined downward at an angle of 15° and 20 feet long was 

 filled with clear Santa Ana River sand. This sand contained practi- 

 cally no fine material and only traces of organic matter. Yet this 

 flume, like the others described above, gave free water at the lower 

 end of the flume, and within a week from the time the experiment 

 was started. 



It would seem, therefore, from the evidence of the ventilated wicks 

 and flumes filled with types of soil from very coarse sand to fine 

 clay and all giving off free water, that the capillary siphon, as above 

 styled, is perfectly established. 



It would also seem that capillary siphons occurring in nature might 

 not be uncommon and that such siphons, first by capillarity alone, 

 and later assisted by gravity, might cause the swamping of lands. 

 Such a condition might arise if there were a stratum of soil of rather 

 high capillary power and a rather impervious subsoil ; if the upper 

 end of such a soil arrangement were in contact with a body of water 

 and the water did not have to be lifted too far by capillarity, and 

 from that point the soil and subsoil had a slope downward at an angle 



