Latest / Timbuktu: Africa's Forgotten Center of Knowledge — Fexingo History / Timbuktu's Islamic Astronomy Innovations
Transcript
- Lucas: So, we've talked a lot about the scholars and the manuscripts, but I want to zoom in on something really specific today — the actual tools and techniques Timbuktu's astronomers used. Not just theory, but the nuts and bolts. Luna: Oh, I love that. Like, what did they actually do when they looked up at the sky? Lucas: Exactly. And the key figure we need to start with is Muhammad al-Wangari, who we've mentioned in a couple of earlier episodes. He was a 17th-century scholar at Sankore, and he wrote a huge astronomical encyclopedia called Mir'at al-'Alam — 'The Mirror of the World.' But today I want to focus on the practical side: how he and his colleagues used instruments like the astrolabe and the torquetum. Luna: A torquetum — that's the device that measures angles in three dimensions, right? Lucas: That's it. It's like an astrolabe on steroids. The astrolabe gives you the position of stars and planets relative to the horizon, but the torquetum lets you work in equatorial, ecliptic, and horizontal coordinates all at once. Al-Wangari described how to build and use both, and he adapted them for the latitude of Timbuktu — around 16.8 degrees north — which meant recalculating all the standard star tables from the Mediterranean world. Luna: So he didn't just copy European or Arabic tables; he made his own? Lucas: Absolutely. And that's the part that often gets overlooked. The standard tables — like the Toledan Tables from al-Zarqali in 11th-century Spain — were calibrated for latitudes around 40 degrees north. Al-Wangari had to adjust them for the Sahel. He also corrected errors he found in earlier works. In his manuscript, he explicitly says, 'I found that the calculation of the lunar eclipse for the year 1017 of the Hijra — that's 1608 CE — was off by half an hour, so I recalculated it.' Luna: Half an hour is a big deal for something like an eclipse. Lucas: It is, especially because eclipses were used to check the accuracy of calendars — and in a Muslim society, the calendar determines Ramadan, prayer times, and the pilgrimage. So getting it right wasn't just academic; it had real religious and social weight. Al-Wangari also wrote about using lunar eclipses to determine the longitude of Timbuktu relative to Fez and Cairo. He'd note the time difference between when an eclipse was observed in different cities and use that to calculate the distance. Luna: So he was doing something like longitude determination, centuries before the British solved it with chronometers. Lucas: Exactly. And the method was theoretically sound — time difference equals longitude difference. The challenge was having accurate clocks. But al-Wangari and his colleagues used water clocks — clepsydras — to measure time during the night. We mentioned al-Kabari's water clock in an earlier episode, but al-Wangari actually designed his own version specifically for astronomical observations. He describes it in Mir'at al-'Alam: a bowl with a hole at the bottom, marked with hours, and you float it in a larger basin. As water seeps in, the bowl sinks, and you read the time on a scale. Luna: Low-tech but clever. And I imagine they had to calibrate it for the season, since water flow changes with temperature. Lucas: Right, and he accounts for that. He also talks about the astrolabe's use for finding the qibla — the direction of Mecca. That was one of the main practical applications. In Timbuktu, the qibla is roughly 67 degrees east of north. But there was debate among Maliki jurists about the exact calculation. Al-Wangari waded into that, using spherical trigonometry to argue for a more precise bearing than the traditional approximation based on the direction of the setting sun. Luna: So he's combining astronomy with fiqh. That's a nice example of how science and religion worked together. Lucas: It's the norm in this tradition, really. The scholars at Sankore saw astronomy as a religious duty — because without it, you can't determine the prayer times or the start of Ramadan. Al-Wangari's book includes tables for the times of the five daily prayers in Timbuktu throughout the year, calculated to the minute. He also gives instructions for building a sundial that works at that latitude — which is tricky because the sun's path is very high in the sky near the equator. Luna: I'd love to see one of those sundials. Do any survive? Lucas: Not many, but we have descriptions. And we have several manuscript copies of Mir'at al-'Alam in the Ahmed Baba Institute and the Mamma Haidara Library. They're in beautiful Maghribi script, often with diagrams of the astrolabe and the torquetum. Some copies even have annotations by later readers — students who checked the calculations or added their own observations. So there's a living tradition of use, not just a dusty text. Luna: That's amazing — it's like having the lecture notes of a 17th-century professor. Lucas: Exactly. And it reminds us that Timbuktu wasn't an isolated outpost. Al-Wangari was in correspondence with scholars in Fez and Cairo. He refers to the works of Ibn al-Shatir, the 14th-century Syrian astronomer who built the most advanced astrolabe of his time, and to al-Zarqali's Toledan Tables. He was part of a global conversation — even if later European narratives tried to erase that. Luna: It's so frustrating that for centuries the Western story was 'Timbuktu had no written science.' And here they were doing cutting-edge astronomy. Lucas: Right. And you know, this connects to something else. This kind of scholarship is fragile. Manuscripts burn, libraries get looted, traditions die if they're not passed on. Which is why I'm really glad that people who care about these stories — people like our listeners — help keep this work going. Luna: Absolutely. This show is ad-free, and it's entirely listener-supported. A couple of dollars a month — the price of a coffee — genuinely makes a difference in whether we can keep researching and producing episodes like this. Lucas: If you've been stepping into history with us episode by episode, and you've gotten something out of these conversations about West Africa, consider throwing a few dollars our way at buy me a coffee dot com slash fexingo. Every bit helps, and there's no pressure — just know that it's what keeps the show going. Luna: Alright, back to the stars. So after al-Wangari, did his tradition continue? Lucas: It did, though the political upheavals of the 17th century — the Saadian invasion and the decline of Songhai — made it harder. But we have evidence of later scholars in the 18th and 19th centuries still using his tables and updating them. One fascinating figure is Muhammad al-Kunti, a Qadiriyya shaykh who wrote a commentary on Mir'at al-'Alam and added new observations from his own study of the stars. So the line of transmission continues, right up to the colonial period. Luna: And now those manuscripts are being digitized, so anyone in the world can access them. Lucas: Exactly. Projects like the Tombouctou Manuscripts Project have digitized thousands of pages. So al-Wangari's work — his careful calculations of eclipses, his sundial designs, his qibla tables — are available to anyone with an internet connection. It's a recovery of knowledge that was nearly lost, and it's a reminder that the history of science isn't just a European story. Luna: I love that we can end on that note — the recovery. Thanks, Lucas.