Stellar Display Tanks

Some spec tech becomes familiar to sf readers.

Dominic Flandry shows a young woman around Admiralty Center:

"He didn't tell her that [the plotting tank's] spectacular three-dimensional star projections were mainly for visitors. The smallest astronomical distance is too vast for any pictorial map to have much value. The real information was stored in the memory banks of unpretentious computers which the general public was not allowed to look on."

-Poul Anderson, The Rebel Worlds IN Anderson, Young Flandry (Riverdale, NY, 2010), pp. 367-520 AT CHAPTER TWO, p. 379.

 

"Cajal gestured with a flashbeam. It probed into the darkness of a display tank, wherein gleamed points of luminance that represented the stars of this region. They crowded by thousands across those few scaled-down parsecs, a fire-swarm out of which not many men could have picked an individual. Cajal realized his talent for doing this had small intrinsic value. The storage and processing of such data were for computers. But it was an outward sign of an inner gift."

-The People Of The Wind, VII, p. 512.

"The computers had just corrected the display tank according to the latest data. It indicated sun, planets, and color-coded sparks which stood for ships."

-ibid., p. 517.

"A new cluster of motes appeared in the tank. Their brightnesses indicated ship types, as accurately as analysis of their neutrino emanations could suggest."

-ibid., p. 518.

Hundreds of James Blish's Okie flying cities orbit a star. John Amalfi, Mayor of New York, stands alone in the ancient reception chamber of City Hall where he is surrounded by banks of screens showing other mayors, a local trader and a cop. Amalfi appears on screens in other cities and spaceships but no one sees that:

 

the New York city manager talks to him through a vibrator embedded behind his right ear;

 

Amalfi, able to speak without moving his lips, whispers into throat mikes hidden behind a high military collar;

 

the apparent desk in front of him is a camouflaged auxiliary battle tank, a three-dimensional chart with moving color-coded lights representing sun, cities and spaceships, not to scale but in their relative positions.