Besides these confused joints there are usually other more regular division planes, which intersect the strata in some definite directions, and run parallel to each other, often over a wide area: these are called master-joints.
"Geology"
James Geikie
The lines of cleavage are seen at D, D, cutting across the planes of bedding and jointing.
"Geology"
James Geikie
40. How may planes of bedding sometimes indicate a break in the succession of strata?
"Geology"
James Geikie