Metal Gallery

DEC PDP-1 computer

DEC PDP-1 computer, on display at the Computer History Museum, USA, with take-away food and drink. Developed by DEC (Digital Equipment Corporation) in 1960, this 18-bit computer cost $120, 000. It was used for laboratory equipment control and for international telephone message- switching systems. The museum's collection includes over 3000 artefacts from 1945 to 1990. Established in 1996, the museum preserves and returns to working order, computers that have had a significant historical impact. The museum is due to be relocated, becoming part of the NASA Research Park, California, USA, in 2005

© VOLKER STEGER/SCIENCE PHOTO LIBRARY

Newtonian Earth, conceptual artwork

Newtonian Earth. Conceptual artwork of the Earth as one of the balls in a Newton's cradle. This image can represent concepts such as the impact and effect of physical laws on the Earth's environment. A Newton's cradle device consists of a number of steel balls suspended from a frame (not seen) in a horizontal line. Here, one ball on the end (left) has been pulled back and allowed to swing forward and downward under gravity. When it impacts the stationary line of balls, its momentum is transferred along the line, causing the ball on the opposite end to move upwards to a similar height. This sequence of impacts continues until all the initial energy has been lost to friction and sound

© DETLEV VAN RAVENSWAAY/SCIENCE PHOTO LIBRARY