Escapement a statue of an angel to follow the sun, the consensus is that this was not an escapement. The first mechanical escapement, the verge escapement, was used in a bell ringing apparatus called an "alarum" for several centuries before it was adapted to clocks. In 14th-century Europe it appeared as the timekeeper in the first mechanical clocks, which were large tower clocks. Its origin and first use is unknown because it is difficult to distinguish which of these early tower clocks were mechanical, and which were water clocks. However, indirect evidence, such as a sudden increase in cost and construction
Controlled internal drug release Controlled internal drug release Controlled internal drug release (CIDR) devices are used in livestock for the synchronization of estrus. They are T-shaped devices with a silicone-coated nylon core. The silicone coating is impregnated with progesterone. CIDRs are inserted intra-vaginally using a specialized applicator. The flexible wings collapse for facilitated insertion and expand once placed appropriately within the vagina. The expansion of the wings retains its position; CIDRs have very high retention rates that may exceed 97%. A thin nylon tail remains exteriorized and is used for removal. Once inserted, CIDRs provide slow-release administration of progesterone, which artificially extends the luteal