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AGRICULTURE: E. C. MILLER 
fall plowed and irrigated with approximately 8 inches of water. The 
crops were surface planted in rows 44 inches apart. After the plants 
were a few inches high the corn was thinned to a distance of 2 feet be- 
tween the plants, Blackhull kafir to feet and the Dwarf milo to 1 
foot. The plots were scraped with a hoe to keep the weeds down but no 
other cultivation was given during the growing season. The plots re- 
ceived no water after the fall irrigation, except that which came from the 
rainfall. 
Leaf Sampling. — The amount of water and dry matter in the leaves 
of a given variety of plant was determined every two hours from 30 leaf 
samples, each with an area of 1 sq. cm. Thirty representative plants 
of each variety were selected and a leaf chosen on each plant for furnish- 
ing all the samples for an experiment extending over the desired length 
of time. At 7 a.m. a single sample was taken from each of the 30 selected 
leaves toward their tips. This was done by means of a Ganong leaf 
punch with an area of one square centimeter. At 9 a.m. a sample was 
taken from each of the 30 leaves directly opposite the sample taken at 
7 a.m. At 11 a.m. the samples were collected from the leaves directly 
below those taken at 7 a.m. and then at the next two hour period directly 
opposite these and so on. The samples for a forty-hour experiment 
were thus obtained from a portion of the leaves representing less than 6 
inches of their respective lengths. The leaf samples from corn, kafir and 
milo at any period could be collected in the manner described in from five 
to eight minutes. Care was taken in the selection of the leaves, so that 
they would be as nearly the same age as possible for the three plants. 
The uppermost, fully-developed leaf of each plant was the one from 
which the leaf samples were obtained. 
The samples were collected in weighed vials which were then quickly 
stoppered. The vials containing the moist material were weighed at 
once on balances sensitive to one tenth milligram. They were then 
placed in a drying oven at 100-105°C. until all the moisture was driven 
off. After drying, the samples were cooled in a desiccator over sulphuric 
acid and weighed so that the amount of water and dry matter could be 
obtained. 
Results. — Nine experiments were conducted in 1914, tw^o in 1915 and 
four in 1916. Four of the experiments in 1914 extended only through 
the daylight hours but all of the other experiments ranged in length from 
twenty-four to forty hours. In all the amount of water and dry matter 
in the leaves was determined every two hours for twenty-two days and 
ten nights. The amount of water in the leaves at any period of the 
night could be accurately determined owing to the fact that dew is very 
