Anchor escapement gear teeth, and inaccuracy. It can also cause the points of the escape wheel teeth to dig into the pallet surface. The teeth are slanted backward, opposite the direction of rotation, and the surface of the pallets is slightly convex, to prevent this. Another reason the escape wheel teeth are slanted backward is as a safety measure. If the clock is moved without immobilising the pendulum, the uncontrolled swinging of the pendulum can cause the anchor pallets to collide violently with the escape wheel. The slanted teeth ensure that the flat faces of the anchor pallets hit the sides of
Controlled-release fertiliser Controlled-release fertiliser A controlled-release fertiliser (CRF) is a granulated fertiliser that releases nutrients gradually into the soil (i.e., with a controlled release period). The slowness of the release is determined by the low solubility of the chemical compounds in the soil moisture. Since conventional fertilisers are soluble in water, the nutrients can disperse quickly as the fertiliser dissolves. Because controlled-release fertilisers are not water-soluble, their nutrients disperse into the soil more slowly. The fertiliser granules may have an insoluble substrate or a semi-permeable jacket that prevents dissolution while allowing nutrients to flow outward. The Association of American Plant Food Control