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
Singing bird box In some movements the flapping of the bird's wings and its ability to turn its head are also cam-controlled, in others not. The final cam determines the point at which the song ends, the bird folds away, the lid drops and the motor stops. The bird's beak movements are always connected to the cam controlling the air supply to the whistle: in this way the sound and beak movements are automatically synchronized. The whistle consists of a miniature organ pipe containing a close-fitting piston which can be moved up and down to give a range of notes of over an