EXPERIMENT STATION BULLETINS. 



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again. At the end of 48 hours the blocks could be placed in the wall 

 but it was found better to allow them to stand 10 days before placing 

 in wall. 



To reinforce the wall a No. S wire was laid in the mortar above every 

 alternate tier. 



As soon as the wall was constructed the inner surface received a 



Fig. 18. Hollow cement block silo, constructed and 

 owned by Wm. Stoll, Lansing, Mich. 



1/^ inch coat of plaster of rich cement mortar, sand and cement in the 

 proportions of 2 to 1. 



A 4 inch cement floor was also put in. 



Mr. Melvin Weeks, who has had much experience in concrete work, 

 thinks that with the style of portable mold used in this work he can, 

 with the aid of two good men, make one hundred 10 inch x 32 inch x 8 

 inch blocks in 10 hours. 



This silo was three weeks in building and filling was begun two days 

 after its completion. A few weeks, at least, should elapse after the 

 completion of such a silo before it is filled. Filling the Weeks' silo so 

 soon, resulted in a crack over each doorway. Three old hoops belonging 



