44 Nebraska Agricultural Exp. Station, Research Bui. 6. 
requirements. These have been described in previous publications, 
but for convenience and a few slight modifications will be assembled 
and restated here. 
In the field experiments the potometers stood in walled-up pits 
of such depth that their tops were on a level with the adjoining 
field. This field was planted to corn and furnished rather normal 
cornfield surroundings. 
POTOMETER WITH COIL-WATERING DEVICE.i 
The type of potometer illustrated below (Fig. 2) was designed 
for experiments where uniform partial soil saturation or frequent 
weighings were desired. To be exact, it was used in all soil satura- 
tion experiments during 1910, 1913, and 1914, and in the 1911 
soil fertility experiment. All hourly and daily correlations in the 
field with climatic factors were made with the corn plants growing 
in this type. 
Fig. 2. — Potometer with coil-watering device. A, galvanized-iron pot filled 
with soil; B, perforated coil for distributing water; C, 6-quart can to 
which water is added; D, galvanized-iron lid; E, 3-inch gravel mulch. 
1 This type of potometer was first used and described by Kiesselbach and 
Montgomery (1911). 
