The primary function of bibliographic citations is to assist the reader in finding the sources used in the writing of a work. To these basic citations, the annotated bibliography adds descriptive and evaluative comments (i.e., an annotation), assessing the nature and value of the cited works. The addition of commentary provides the future reader or researcher essential critical information and a foundation for further research.
French drain. A French drain or weeping tile (also blind drain, rubble drain, rock drain, drain tile, perimeter drain, land drain, French ditch, sub-surface drain, sub-soil drain or agricultural drain) is a trench filled with gravel or rock or containing a perforated pipe that redirects surface water and groundwater away from an area.
French drains are quite simple: in essence they are just trenches filled with gravel, with sand on top of that. Often, you'll see French drains defined to include a drain pipe as well, though the traditional design is simply the gravel-filled trench. The advantages of French drains are low cost and easy installation. In addition, they can be covered over with turf after installation, making them less conspicuous. 1  Dig the trench.