190 Report OF THE HORTICULTURIST OF THE 
thoroughly soldered in. The latter was ordered an inch larger in 
diameter than the cylinder, and its outer edge was bent into a 
flange half an inch wide. It was inserted with the flange pointing 
outward, as a boiler head is usually put in, which made it possible 
to nail it in securely before the soldering. The space between the 
copper bottom and the end of the cylinder was then filled in with 
a false bottom, made of half inch boards, after which the plank 
bottom was put on and securely fastenedsby means of the angle 
irons. ‘The cylinder was then laid down, rolled to the pit and 
lowered to its position by means of an inclined plane and an 
extemporized windlass. The tube connecting the drain pipe with 
the lysimeter pit was then inserted through the wall and soldered 
at the point E. 
The apparatus for supplying the water is somewhat different 
from that described in our: last report, and may need some 
explanation. Fis a graduated glass vessel holding 1,000 cubic cen- 
timeters. The bottom is stopped by arubber cork, through which 
pass two slender tubes, which connect at their lower end with the 
four-way brass stop-cock G. Below this the tubes are continued 
into the mouth of the drainage tube C, which turns upward, form- 
ing an elbow inside the lysimeter pit. At H is another stop-cock, 
which is placed on a line with the upper side of the drainage tube 
©, and which, so long as it is open, limits the depth of water in 
the bottom of the lysimeter. It will be observed that of the two 
slender tubes that pass downward from the stop-cock G, the 
right hand one comes to an end opposite the drainage-cock H, 
while the other one extends somewhat farther. 
Let us now suppose the water in the bottom of the lysimeter to 
be on a level with the open drainage-cock H, and the four-way cock 
G to be turned so that the holes through the pin form a passage 
from the reservoir F into the drainage tube C. If now there is 
percolation from the soil of the lysimeter, the water percolated flows 
out through the drainage-cock H and is collected in the bottle 
beneath it. If, on the other hand, the soil of the lysimeter 
absorbs some of the bottom water, the level of the latter falls, 
permitting a bubble of air to enter the slender tube at I, which, 
passing upward through the cock G, is conducted into the upper 
part of the reservoir F. This allows an equal bulk of water to pass 
