writing instruments [4]

The first true writing instruments were made by the Sumerians in Mesopotamia nearly 5,000 years ago.

ballpoint pen

Instrument invented at the beginning of the 20th century; the writing tip holds a small rotating ball.

point

Tip that contains the ball bearing used to deposit ink from the cartridge onto the writing surface.

joint

clip

Curved metal bar that attaches the ballpoint pen to a pocket.

push-button

Button controlling the mechanism that advances and retracts the cartridge.

spring

Elastic metal part that compresses to push the refill out and relaxes to retract it.

thrust tube

Part that is activated by the push-button; it pushes out or retracts the writing tip when pressure is applied.

thrust device

Protruding part that locks the thrust tube in a forward or retracted position.

cartridge

Small reservoir containing ink and ending in a point.