of a wall it should also be noted that in the preferred embodiment portions of each block end come in contact with an adjacent block this allows for proper alignment and spacing which maximizes amount of bonding material to attach between each unit to strengthen the bond it should also be noted that preferably the shape of the intermediate vertical cavity 40 is irregular this configuration increases the surface area available for the bonding material to attach to for a stronger bond this configuration also ensures that the end projections 14 each attach around the cured bonding material contained in the vertical cavity 40 which further reduces the possibility of a breach in the wall even if the bonding material should become separated from the associated masonry unit as shown in fig1 and 4 the masonry unit 100 can include one or more vertical depressions 15 in one or both of the side surfaces 11 preferably each vertical depression 15 has a width greater than one half inch and less than two inches preferably each vertical depression 15 projects into the masonry unit 100 between one half inch and two and a half inches and each vertical depression 15 also preferably.