cost of up-keep and permanence. The initial cost will vary largely 

 according to the price of sand and gravel or crushed rock used as 

 aggregate for the mixture. 



Showing proportion of farmers who construct certain kinds of concrete work, and those 

 who have the same work done by exrert mechanics who follow such work as a vocation. 



A conclusion of educational value to be drawn from the facts 

 shown in Figure 5 and in Table 8, is that cement and concrete work 

 deserves a place among the materials used in teaching farm shop 



28 



