Silos and Silage in Colorado. 
33 
pared were also furnished by Mr. Risser. The drawings upon 
which figures i to 11 are based were prepared by Mr. Maris. 
The cuts used in illustrating these instructions were loaned by 
The Colorado Farmer. 
Laying Off Ground for Excavation .—Figure i illustrates the 
manner in which the ground may be laid off preparatory to exca¬ 
vation for the silo. The center stake (a) should be well set into 
the ground and a straight stiff scantling (b) long enough to reach 
past the outside wall of the silo should be spiked to this with a nail 
that will not bend easily. The nail marks the center of the silo. 
From this center nail measure the distance to the outside of the silo 
wall and mark across the scantling at this point. Nail a block (c) 
flush with this mark. A sharpened board (d) may then be held 
against this block and be raised and lowered to meet the irregu¬ 
larity of the ground as the circle is described. The scantling (b) 
should be kept level while the circle is being described. 
In case the silo is to be 16 feet in diameter the point of the 
sharpened board should mark off a circle just 8 feet and 6 inches 
from the center nail, the 6 inches being allowed for the silo wall. 
The dirt inside the circle thus described may then be thrown out to 
the desired depth. 
Depth of Excavation .—The bottom of the silo should not be 
more than 5 feet below the ground level on the side in which the 
door is to be placed. A greater depth will cause inconvenience in 
removing the silage from the bottom of the silo. Care should be 
taken to keep the walls smooth and perpendicular in excavating. 
Irregularity in the dirt walls will result in either large cavities that 
must be filled with concrete or narrow places in the wall. When 
a team and scraper are used in excavating, an exit driveway should 
be left at one side. Hand shovels should be used around the walls 
of the excavation. When the team and scraper have been used as 
long as possible the driveway may then be thrown'out by hand. 
Care should be taken to level the dirt floor of the excavation. 
A spirits level and plumb which will be needed .throughout the con¬ 
struction of the silo, should be used for the purpose and it should 
also be used as a guide in keeping the walls perpendicular while ex¬ 
cavating. 
Footing for Wall .—The walls of the silo should rest upon a 
solid foundation or footing extending below the frost line. The 
size of this footing will be regulated by the nature of the dirt in 
which the excavation is made. One foot and a half deep by 16 to 
20 inches wide at the bottom will be sufficient in case the dirt 
is solid. If the soil is loose and sandy a larger footing should be 
