Dry rubble masonry: The rubble masonry in which stones are laid without using any mortar is called dry rubble masonry or sometimes shortly as "dry stones". It is an ordinary masonry and is recommended for constructing walls of height not more than 6 m. 
    Three types of Rubble Masonry are as follows: 
    (a)    Un-coursed Random Rubble Masonry: The random rubble masonry in which stones are laid without forming courses is known as un-coursed random rubble masonry. This is the roughest and cheapest type of masonry and is of varying appearance. 
        It is used for the construction of walls of low height in the case of ordinary buildings. 
    (b)    Coursed Random Rubble Masonry: The random rubble masonry in which stones are laid in layers of equal height is called random rubble masonry. In this masonry, the stones are laid in somewhat level courses. Headers of one coursed height are placed at certain intervals. The stones are hammer dressed. 
    (c)    Squared Rubble Masonry: The rubble masonry in which the face stones are squared on all joints and beds by hammer dressing or chisel dressing before their actual laying is called squared rubble masonry.