The most widespread type of masonry work is the erection of solid brick masonry using individual bricks set in mortar. âLight masonry,â consisting of two parallel face walls each one-half a brick thick and filled with a light concrete, loose slag, or another insulating material, is sometimes used.
A sinkhole, also known as a cenote, sink, sink-hole, shakehole, swallet, swallow hole, or doline (the different terms for sinkholes are often used interchangeably), is a depression or hole in the ground caused by some form of collapse of the surface layer.
Cylindrical cuts into river rock are also called potholes, sometimes kettle holes, and are due to erosion of the rock over eons of time. To fishermen, it can be a good area for angling. Where geology and time have dried up those beds, chasms remain.