COSTCKETE SILOS. 27 



cobble stones, place standards of scantling long enough 

 to extend twelve inches higher than the top of the wall 

 when it is finished. Place these standards on each side 

 of the proposed wall, and if you desire the wall to be 

 twenty inches thick, then place the standards twenty- 

 three inches apart, and place a pair of standards every 

 five or six feet around the entire foundation. Be par- 

 ticular to have these standards exactly plumb and exactly 

 in line. Fasten the bottoms of the standards firmly in 

 the ground, or by nailing a strip of wood across at the 

 bottom of the standards, and a little below where the 

 floor of the silo will be. Fasten the tops of the stand- 

 ards by a heavy cross-piece, securely nailed, and fasten 

 the pairs of standards in their plumb position by shores 

 reaching the bank outside. Now take plank, one and a 

 half inch thick and fourteen inches wide, and place them 

 edgeways inside the standards, twenty inches apart, thus 

 forming a box fourteen inches deep, and running all 

 along and around the entire foundation of the proposed 

 wall. Fill this box with alternate layers of cobble stone, 

 or any rough stone, etc., and mortar or concrete. First, 

 a layer of concrete mortar, and then a layer of stone, 

 not allowing the stones to come quite out to the boxing 

 plank, but having concrete over the edges, and the con- 

 crete must be tamped down solid. Prepare the concrete 

 as follows : Take one part of good cement, Portland is 

 the best probably, and mix with this four parts of sand, 

 and mix the cement thoroughly with the sand while dry, 

 and then mix four parts of clear gravel ; make into a 

 thin mortar, and use at once. Put into the box an inch 

 or two of this mortar, and then bed in cobble stones ; 

 then fill in with mortar, again covering the stones, and 

 again put in a layer of stone. When the box is filled 

 and the mortar "set," so that the wall is firm, then raise 

 the box one foot, leaving two inches lap of plank on the 

 wall below, and go around again, raising the wall one foot 



