




183 
Total differences of Total Total 
For the week ending wet and dry bulb. absorption. rainfall. 
Sept. 11....100.1 degrees 203% cubic cent. .10 inches. 
Seep G60. tf Dye ON ee i} Wig. 
dave g's. 260, ¢46.7, 5). Arto ruiyac git 1980 oes 
; LC buds tise cc 43: 0 tS Tey ibe 40 fs 
Bae SAG. T joo 3 ay Aiea Muy cana 
(oe atnvsy) ) ehOl a. 83.3 os 35'5 ae NG bg aA ah 
*.13 inch of rain fell during the last day 
as it affected but a single reading. 
It is clear from this table that the absorption diminished 
nearly in proportion to the diminution of the differences of 
the wet and dry bulb, and that during the week of excessive 
rain, it was correspondingly less. We should expect that 
in general terms, the moisture of the soil would have some 
relation to that of the air during weekly periods, and the 
table shows that a relation did exist between the moisture 
of the air and the absorption by the soil, though it was 
modified by the rainfall, which is also as we should expect. 
Several other experiments conducted in the office with 
similar apparatus, using bottles of soil, gave additional 
evidence of the feasibility of this method for recording the 
soil moisture. The effects of temperature and other modi- 
fying influences upon the absorption, as well as a method 
for calculating the actual moisture from the readings of the 
apparatus remain to be worked out. 
f 
° 
ct 
he trial, but this isnot noted, 
THE COMPARATIVE MOISTURE OF CULTIVATED GROUND AND 
SOD IN SUMMER WEATHER. 
Out of many tests of the soil moisture made by drying 
actual samples of soil, a single series is reported, indicating 
the difference in the percentage of water contained in cul- 
tivated ground and sod, in moderately dry summer weather. 
The cultivated soil had produced a crop of peas early in the 
season, but the vines had been removed several days before 
the tests were commenced. The sod was in an orchard of 
young apple trees, but the samples were taken from a part 
not in the least shaded by the trees, and as far from them 
as possible. A crop of grass had been removed from it in 
June, and the second growth was three or four inches high 
at the commencement of the test. The cultivated soil was 
the more fertile of the two. The tests were commenced 
Aug. 23, the last rain (.58 inch) having fallen Aug. 16. 
The samples were taken by means of an instrument re- 
sembling a butter tester, the blade being inserted to the 
depth of six inches. After drying, the samples were washed 
through a sieve of one-tenth inch mesh, the stones and. 
other substances that would not pass through the seive be- 
ing then dried, and their weight deducted both from that of 
the fresh and dried sample. 
13 
