A rare gilt brass astrolabe by Christoff Schissler is to auction with an £80,000-120,000 ($119,170-178,756) estimate at Bonhams London on May 19.
Schissler (circa 1531-1608) was a renowned engineer and instrument maker who produced a huge range of scientific devices over the course of his career.
His work was hugely popular among the noble families of Europe. The present lot was produced in Augsburg, Germany in 1566.
Bonhams describe the lot as "an apparently unrecorded instrument by Schissler which is entirely coherent with his production…
"Today about 100 instruments from the Schissler workshop are recorded and are exhibited in the national collections located in Oxford, London, Vienna, Prague and Florence."
A large terrestrial globe made by Vincenzo Coronelli in the mid 17th century is valued at £60,000-80,000 ($89,378-119,170).
Bonhams explains that Coronelli was "considered by many to be the pre-eminent globe maker of the period, at the age of 15 became a novice in the Franciscan Order and also trained as a wood engraver.
"He eventually became the official cosmographer of the Republic of Venice and wrote more than one hundred works of terrestrial and celestial cosmography in Latin, French and Italian."
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