How many angels can dance on the head of a pin? dancing on a needle's point occurs in an expository work by the English divine, William Sclater (1575-1626). In "An exposition with notes vpon the first Epistle to the Thessalonians" (1619), Sclater claimed that scholastic philosophers occupied themselves with such pointless questions as whether angels "did occupie a place; and so, whether many might be in one place at one time; and how many might sit on a Needles point; and six hundred such like needlesse points." Harrison proposes that the reason an English writer first introduced the "needle’s point" into a critique of medieval angelology is that it makes for
Preening (bird) bathing, dusting, sunning, oiling or anting, and can either precede or follow these other behaviours.Preening typically involves an action between its beak and claws on its foot. Because fully-grown feathers are essentially dead structures, it is vital that birds have some way to protect and lubricate them. To facilitate this, many species have a preen or uropygial gland, which opens above the base of the tail feathers and secretes a substance containing fatty acids, water, and waxes. The bird gathers this substance on its bill, and applies it to its feathers. The gland is generally larger (in relation to body