This set of four stamps were published in URUGUAY in 1998 as part of the Expanding youth's horizons series: The first stamp features a stone ax and a megalithic monument, earning it a spot in this collection. The wheel and pyramid, the printing press and solar system, a satellite and a flow diagram, are featured on the other three stamps in the set.

"Putting Their Stamp On The Future"

ST390143477417mkk820