Latest / Timbuktu: Africa's Forgotten Center of Knowledge — Fexingo History / The Timbuktu Scholar Who Calculated the Width of the Red Sea
Transcript
- Lucas: Welcome back, Luna. Today we're picking up a thread we touched on in a few earlier episodes — the scientific side of Timbuktu's scholarly tradition. We've talked about medicine, about law, about history writing. But one figure we haven't given a full episode is Muhammad al-Wangari, the astronomer who wrote 'Mir'at al-'Alam' — 'The Mirror of the World'. Luna: I remember we mentioned him in the episode about calculating the moon's orbit. But what exactly is in that manuscript? Lucas: It's a full astronomical handbook. Al-Wangari was working in the late 17th century — around 1680 or so — and he compiled tables for calculating the positions of the sun, moon, and planets, as well as methods for predicting lunar eclipses. What's fascinating is that he wasn't just copying earlier work; he was actively adapting it to Timbuktu's latitude, which is about 16.8 degrees north. Luna: So he was doing original calculations, not just translating? Lucas: Exactly. The manuscript shows he used the work of earlier Islamic astronomers like al-Zarqali from 11th-century Andalusia — whose Toledan Tables were famous across the Islamic world — and al-Battani from 9th-century Syria. But al-Wangari adjusted their data for his local coordinates. He even calculated the width of the Red Sea, which suggests he had access to detailed geographical knowledge from both the Mediterranean and Indian Ocean trade networks. Luna: That's impressive. But how did a scholar in Timbuktu get access to all these works from North Africa and the Middle East? Lucas: The same way they got everything else — the trans-Saharan trade. Manuscripts from Cairo, Fez, and even Baghdad made their way to Timbuktu's markets and libraries. We know from the Tarikh al-Sudan that wealthy merchants would bring back books alongside salt and gold. And Sankore University had a curriculum that included astronomy, mathematics, and geometry alongside the religious sciences. So al-Wangari would have studied these texts as a student, then built on them as a teacher. Luna: Did he use instruments like an astrolabe? Lucas: He certainly did. There are references in the manuscript to observations made with an astrolabe, which is a kind of analog computer for solving problems in astronomy. We know from other sources that astrolabes were manufactured in Timbuktu itself — not just imported. There's a surviving example from the 18th century that was made locally, inscribed in Arabic with the names of the constellations. So al-Wangari had the tools to make precise measurements. Luna: And he used those measurements to predict eclipses? Lucas: Yes. The 'Mir'at al-'Alam' includes a table of lunar eclipses covering several decades, calculated for Timbuktu's sky. That's incredibly practical — knowing when an eclipse would happen was important for setting the Islamic lunar calendar, because the new moon marks the beginning of each month. And a lunar eclipse can confirm that the moon is full, which helps determine dates for religious festivals like Ramadan. Luna: So astronomy and religion were closely connected. Lucas: Absolutely. And that's why the ulama — the religious scholars — were often also astronomers. At Sankore, the curriculum in Maliki fiqh included the study of celestial movements, because you needed to calculate prayer times and the direction of Mecca. Al-Wangari's work was seen as a tool for piety, not a separate discipline. Luna: How did his work compare to European astronomy at the same time? Lucas: That's a great question. In the late 17th century, European astronomy was undergoing the Scientific Revolution — Newton was about to publish his Principia in 1687. Al-Wangari was working in the Ptolemaic tradition, with Earth at the center, so he wasn't using heliocentric models. But his calculations were accurate enough for practical purposes. And his work shows that Timbuktu was not isolated from global scientific currents — it was a node in a network that stretched from Andalusia to the Indian Ocean. Luna: Were his manuscripts preserved? Lucas: Yes, copies of 'Mir'at al-'Alam' survive in several libraries, including the Mamma Haidara Commemorative Library and the Ahmed Baba Institute in Timbuktu. In fact, during the 2012 crisis, when militants occupied the city, these manuscripts were smuggled to safety in Bamako — we covered that in episode 94. The al-Wangari manuscript was among those saved. Today, it's been digitized and is available for scholars worldwide. Luna: So we can actually read his work now. That's amazing. Lucas: We can. And what's striking when you read it is how practical it is — it's not just theory. He gives worked examples of how to calculate the altitude of the sun at noon in Timbuktu on any given day. He provides tables of the equation of time, which corrects for the difference between apparent solar time and mean solar time. This is stuff that a student at Sankore could actually use. Luna: It makes you wonder how much else is still hidden in those libraries. Lucas: That's exactly the point. The manuscripts of Timbuktu are a vast, largely unexplored archive. Al-Wangari is one name among hundreds. There are texts on algebra, on optics, on medicine — many of them still not fully catalogued. And that's part of why we do this show — to share the stories that have been overlooked. Luna: Speaking of which — if you're coming with us through these conversations about West Africa's intellectual heritage, and you'd like to help keep these stories ad-free and accessible, listeners can support the show at buy me a coffee dot com slash fexingo. It's a way to say that deep dives like this one matter. Lucas: Yeah. And every bit of support helps us spend more time on research and production. Now — back to al-Wangari. One of the most remarkable parts of his manuscript is a calculation of the circumference of the Earth. He doesn't claim it as his own — he credits al-Battani — but he reproduces it and checks it against his own observations. That shows a scientific mindset, not just blind copying. Luna: He valued verification. Lucas: Exactly. He writes something like 'I have examined this and found it to be sound.' That's the attitude of a scientist. And it's important because it challenges the stereotype that African scholarship was purely religious or derivative. Al-Wangari was an original thinker who engaged critically with his sources. Luna: What happened to his school of astronomy after his death? Lucas: That's a bit murky. Timbuktu's golden age of scholarship began to decline in the 18th century as the trans-Saharan trade routes shifted and political instability increased. But the manuscripts were still copied and studied. We know that scholars in the 19th century were still reading al-Wangari. So his work had a long afterlifet. Luna: And now it's being read by historians of science. Lucas: Yes. And that's a story we'll keep following. Thanks for tuning in.