DR Jan P. Hogendijk, professor of history of mathematics at University of Utrecht, the Netherlands, speaks at Habib University on Tuesday. —Fahim Siddiqi / White Star
DR Jan P. Hogendijk, professor of history of mathematics at University of Utrecht, the Netherlands, speaks at Habib University on Tuesday. —Fahim Siddiqi / White Star

KARACHI: “The best astrolabes in the 17th century were made in the city of Lahore which most people in this country are unaware of,” said Dr Jan P. Hogendijk while speaking at Habib University on Tuesday.

Dr Hogendijk is part of a Dutch team from the department of mathematics, University of Utrecht, the Netherlands, that travels far and wide to educate people about the historical significance of the astrolabe, its uses and the general history of astronomy in mediaeval Islamic civilisation.

There are many uses of an astrolabe, said Dr Hogendijk. It was used at a time when there were no watches, so one of its uses was to determine time. You can also use it to find the direction of the poles, during the day and even at night. During the day you need the sun for it while at night you will need the starts. It is also used in astronomy.

“They started making astrolabes in Lahore in 1560 and continued till 1700s. A family in Lahore became very good in making astrolabes which were more sophisticated than what was being made in the rest of the world,” said Dr Hogendijk.

‘Around 2,000 Islamic astrolabes still exist’

They looked like complex pieces of art but were an accurate representation of the constellations in the sky, he added. All the pieces made were made following precise mathematical measurements and thus were considered to be the best in the world.

The thickness of those plates was only one millimetre and eventually it was decided to investigate what made the astrolabes from Lahore so distinct from any other. Thus a synchrotron was used to examine them. “It was found that the astrolabe made in Lahore had a different metal composition and contained much more zinc than it was assumed to be possible,” he said. “This is part of Pakistan’s heritage and thus more people must know about it.”

Dr Hogendijk, also a professor of history of mathematics, was at the hub of the lecture and he debunked myths regarding astrolabes; for one he insisted that astrolabes were never used for navigation as is widely believed. He criticised the rampant misinformation present on the internet which has misled people into believing this.

Dr Hogendijk said: “There are around 2,000 Islamic astrolabes that still exist. In the golden era of Islam, astrolabes were widely used in society, and their mention is also present in Rumi’s poetry.” He quoted examples from Rumi’s poetry where astrolabes are referenced.

“When we try to access information on astrolabes, we find mostly European sources, even though there is a rich Islamic tradition with regards to astrolabes. This is why we conduct these workshops.”

About the interest Dutch people have in mediaeval Islamic science, Dr Hogendijk said that it is also because “we have in our country one of the best collections of Islamic manuscripts in the world. Since 1630 CE the University Library in Leiden preserves one of the largest collections of mediaeval Arabic manuscripts in the world.”

Dr Hogendijk’s team included Willem Frederik de Graaf and Tom Jon Ester Reijngoudt, who will help him conduct a workshop on the standard astrolabe.

“Each participant in the workshop will receive a model of an astrolabe which is based on the astrolabe by al-Khujandi, which is now in Doha, Qatar. All participants will then solve exercises by themselves.”

Published in Dawn, March 7th, 2018