A crevasse is a deep crack, or fracture, found in an ice sheet or glacier, as opposed to a crevice that forms in rock. Crevasses form as a result of the movement and resulting stress associated with the shear stress generated when two semi-rigid pieces above a plastic substrate have different rates of movement. The resulting intensity of the shear stress causes a breakage along the faces.
Unfortunately, many cyclists choose to ride their bikes at dark without bicycle head lights or tail lights. This is against the law in most states in the U.S. (Amazingly, Washington, Texas, and others only require a head light and rear reflector.) It is also very dangerous.here are at least two primary reasons for you, a bicycle rider, to use lights at night. 1  First, the front head light illuminates the area in front of you, so you can ride safely, by being able to detect any hazards you approach.
Night Hunting: Allowed, Hogs, Coyotes and armadillos may be hunted at night with an artificial light that is carried on the hunter s person attached to a helmet or hat, or part of a belt system worn by the hunter.ight Vision: Not Allowed, per the 2010 Kansas Hunting & Fur harvesting Regulations Summary, Furbearers and coyotes may be taken at night, but use of artificial light, including optics that project or amplify light, is prohibited.