GB1320053A - Apparatus for moistening a mass of soil - Google Patents

Abstract

1320053 Watering plants N CALTAGIRONE 28 April 1971 [28 April 1970] 12022/71 Heading A1E A device for watering plants comprises capillary means 8 for supplying water from reservoir 6 to soil T, capillary tubes 3 connecting the reservoir with the atmosphere, and an auxiliary reservoir 1 linked to the main reservoir by a central channel 4, the tubes 3 communicating with the central channel and via passages 13, 12, 10, with the atmosphere. The removal of water by capillary action through tubes 8 causes a reduction in pressure in the air space of reservoir 1 until an equilibrium is reached between the capillary suction and the reduced pressure, stopping the flow out. When moisture has evaporated from the soil suction resumes and the reduction in pressure once more increases, until atmospheric pressure is able to overcome the surface tension resistance of the water in capillary tubes 3 and air can enter the reservoir. The reduced pressure can therefore be maintained at a fixed value and the amount of moisture absorbed by the soil be governed by the width of the tubes 3, since the narrower the tubes the greater the surface tension resistance. In a modification, capillary tubes of different widths radiate from the central channel 4, the amount of moisture absorbed by the soil being adjusted by a rotatable valve sleeve connecting them selectively with the atmosphere. In further embodiments (Figs. 6-10, not shown) the auxiliary reservoir is omitted and a capillary orifice (35, 41) is inserted below the level of the water on the end of a hollow sleeve (34, 44) removably located in an upper wall of the reservoir. In Fig. 11 capillary means 65 1 ..65 3 communicating with the reservoir R are buried in separate masses of soil, the regulating capillary passages being provided by porous capillary material 62.