COMPOSITION, PROPERTIES, AND TESTS OF PLASTERS. 63 



trued to give a cross-section exactly 1 inch square. These pieces 

 of paving-brick were placed in the cement briquette molds with this 

 true surface exactly at the middle of the mold. The plaster or stucco 

 was placed to fill the other half of the mold, while the half in which 

 the piece of brick was placed was filled with neat Portland-cement 

 mortar ". 



TABLE 16. 

 EFFECT OF SAND ON COMPRESSIVE STRENGTH OF PLASTERS. 



TABLE 17. 

 ADHESIVE STRENGTH OF PLASTERS. 



