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76. Between a Rock and a Hard Place in The Tropic of Cancer during 800 to 900CE

AUG. 24, 2023


Pete takes on a round-the-world challenge and finds himself between a rock and a hard place on the Tropic of Cancer. We discover the surprising product that rated alongside gold in value on the trans-Saharan trade routes and we meet a pair of travelling historians whose journeys took them from Africa to China. Also, learn how a failed rebellion can still bring down a dynasty, and find out how you might apply for your harlot’s license in 9th Century China.

This episode takes Pete and Ryan all around the world on a tour of one of the five main lines of latitude – the Tropic of Cancer.

Also known at the Northern tropic, the Tropic of Cancer is an imaginary line running around the Earth at just over 23 degrees North of the equator.

But what is it, and why is it a thing?

Look at a globe and you might notice it is separated into a grid of lines of latitude and longitude. Longitude are the lines going north/South (or up down if you prefer), and lines of latitude are the ones running east/West or left to right.

There are 360 lines of longitude and 180 lines of longitude, which sounds odd, but I find it helps to think that whilst they are both the same number of circles around the globe, in latitude the line goes all the way around, but in longitude, the two halves are considered different lines. For example, the equator is the equator all around the globe, but the Greenwich meridian only goes from North to South Pole and where the circle continues, that’s a second, different line of longitude.

As you travel across the globe longitudally you change time zones, because this is the way the globe rotates so noon is at one line, it’s midnight on the opposite side.

The Tropic of Cancer is considered an important line of latiitude because it is the most northerly circle of latitude on Earth at which the Sun can be directly overhead, which happens on the June solstice, around June 21st . This is when the Northern Hemisphere is tilted toward the Sun to its maximum extent.

At this time, in astrological terms, the Sun is in the constellation of Cancer, hence the name.

To make it even more confusing, there is a slight wobble in the Earth's tilt, which varies over a 41,000-year period from 22.1 to 24.5 degrees. This wobble means that the Tropic of Cancer is currently drifting southward at a rate of almost half a second (0.468″) of latitude, or 15 m (49 ft), per year.

Cancer is one of the five major circles of latitude that mark maps of Earth. The others are the Tropic of Capricorn – the southern equivalent of Cancer, the Arctic and Antarctic circles – these are the the most northern and southern places where, at least once a year, the sun remains continuously above the horizon for 24 hrs and the Equator aka the middle.

Countries that lie on this latitude, starting at the West coast of Africa are:
• Western Sahara
• Mauritania
• Mali
• Algeria
• Niger
• Libya
• Egypt
• Saudi Arabia
• United Arab Emirates
• Oman
• India
• Bangladesh
• Myanmar
• China
• Taiwan
• Mexico
• The Bahamas

So how big is it? That is a tricky question. We know how long it is - 36,768 kilometres (22,847 miles) long.

But how wide is it. The Pacific islands Ocean Observing System gives it a North Bounding Coordinate of 23.43954° and a South Bounding Coordinate of 23.43934°

Population is a bit of a tricky question. If you take the population of all the countries on the tropic of Cancer, you get 3,438,181,021 or 43% of the world’s population.

As for a national animal, although there is not an official one, you could make a case for the humpback whale, which can be found in various waters all around the belt of the tropic. They typically migrate up to 16,000 km (9,900 mi) each year, can weigh up to 40 tonnes and are great singers, singing songs up to 30 minute long, or 3.2 times a Stairway to Heaven.

Geographically, obviously it’s fairly diverse, but in general it is called a tropic for a reason. It’s hot – at its peak, the sunlight is hitting directly on the ground rather than being spread out over a bigger area. Take a torch, pointing directly at a piece of paper, now angle the paper – the light covers a bigger area right? But the amount of energy is the same, it’s distributed over a wider area. So the climate at the Tropic of Cancer is generally hot and dry.

That said, some coastal areas will be wetter and there are also some cooler highland regions in China.

Most regions on the Tropic of Cancer experience two distinct seasons: an extremely hot summer with temperatures often reaching 45 °C (113 °F) and a warm winter up to around 22 °C (72 °F).

Tropic of Cancer facts:
The Fédération Aéronautique Internationale use the Tropic of Cancer as a shorthand for the whole world - for a flight to compete for a round-the-world speed record, it must cover a distance no less than the length of the Tropic of Cancer. You must also cross all meridians, and end on the same airfield where it started, in case you’re thinking of tackling a round the world aviation record.

In geopolitics, the Tropic of Cancer is the southernmost line covered by the mutual defence treaty of NATO – if your territory is under threat and it’s south of the Tropic of Cancer, too bad.

Famous tropics of cancer – a novel of that name by an American author Henry Miller was published in 1934 Paris, but this edition was banned in the United States.

It is semi autobiographical and relates of the life of a struggling writer in Paris, including explicit scenes of sex and sexuality, which led to its banning.

One person went to jail for three years for importing and selling the book in America although it was legally published in America in 1961, but as soon as that happened, a number of lawsuits were brought against it for obscenity.

This resulted in Pennsylvania Supreme Court Justice Michael Musmanno wrote that the book is "not a book. It is a cesspool, an open sewer, a pit of putrefaction, a slimy gathering of all that is rotten in the debris of human depravity."

It wasn’t just America clutching its pearls either, the book was also banned for a period in Canada, Australia and Finland.

Of course today, you can buy it in all good bookshops and even find the text on the Internet.

About “Between a rock and a hard place”
This is an expression meaning to be stuck between two choices or options, neither of which is very nice. A lot of people say this starts with Homer’s Odyssey, where the hero Odysseus must pass between Charybdis, a treacherous whirlpool, and Scylla, a cliff-dwelling monster.

Other sources have said it originates in America at the start of the 20th century, one claiming it was a mining origin, the rock being tough work in the mine and the hard place being unemployment and penury.

For me, I don’t think it needs that much explaining. I think it’s quite plausible that this is just a modern version of a phrase that is not uncommon because it’s a good shorthand for a fairly common human experience. You might also hear:
o Between the devil and the deep blue sea
o Russians say ‘between the hammer and anvil’
o In more recent popular culture you might talk about– Sophie’s choice
o Or you might be on the horns of a dilemma – two bad choices

So whilst we can credit Homer if we want to sound fancy, I feel like it’s just a useful expression for a common human experience and didn’t really need to be invented by anybody.

And I’m stuck between a rock and a hard place for this episode. I have to choose between featuring just one country that’s found on the Tropic of Cancer and thus get a low grade from Judge Dersley for not covering the area properly, or alternatvely, I can try to cover all the and in turn get a low grade from Judge Dersley for skimming the surface and not being in-depth enough.

So in this episode I’m going to try to encapsulate the place and topic by get from a rock to a hard place, travelling as far as I can along the Tropic of Cancer using methods and people found in our time period, the 9th Century.

Betweeen a rock and a hard place in the Tropic of Cancer, 800 to 900CE

We’re going to start on the West Coast of Africa, where we find the country of Mauritania. Although borders are nothing like they were then, in the 9th century, you don’t have a Mauritania.

What we do have though, is one of the the most dominant empire in West Africa at this time - the Empire of Ghana.

Confusingly, the Ghana empire was not actually near where modern Ghana is today. It’s further North West of modern Ghana, in the bulge of Africa, covering an area where you find Mali, Senegal and Mauritania now.

Around 300CE various tribes of the Soninke people came together and, over generations, grew this empire of Ghana.

Three things really helped that happen, the first two are fairly obvious, the third not so much.

One is trade – somewhere around 200 to 300CE we see the camel starting to be found in the Sahara, specifically crossing the Sahara – initiating a trade that wasn’t found before between North Africa and Sub Saharan Africa. And if you made that journey from North Africa, as it happened, the empire of Ghana was pretty much the first place you arrive . This enabled them to act as ‘middle men’ for the trade between North Africa and the sub-saharan world, greatly enriching them

But as well as trading, the Ghanain empire was blessed with another fairly handy resource – gold.

We know this largely from the writings of the Arab scholars who engaged in or were aware of the cross-Saharan trade.

One of these was Al Yaqubi, an Islamic scholar who died around 897. He wrote a book known as Al Tarikh or History and in it he says:

“there is the kingdom of Ghana, the king of which is very powerful. In his country there are gold mines. Under his authority there are other kingdoms such as ‘am and Sama, and gold is found in all these regions.”

Another Arab traveller of the 9th Century, a man known as Al Masudi, who we’ll meet again later, said: “The kingdom of Ghana is one of great importance, and it ajoins the land of the gold mines. Great peoples of the Sudan live there (meaning black people, rather than the modern country). They have traced a boundary that no-one who sets out to them ever crosses.”

Al Masudi goes on to describe how these people went about negotiating these trades, he says: “When the merchants reach this boundary, they place their wares and cloth on it, then depart, and so the people of the Sudan come bearing gold which they leave beside the merchandise and then depart. The owners of the merchandise then return and if they are satisfied with what they have found, they take it. If not, they go away again, and the people of the Sudan return and add to the price until the bargain is concluded… “

He also goes on to emphasise the wealth of the area, saying: “Under the supreme rule of the king of Ghana there are a number of lesser rulers , and in all their kingdoms gold is visible on the ground, and the people extract it and set it like curds.”

But I know that Dersley is going to tell me that gold is a metal, not a rock, and I need to find us a rock to get us started on our journey.

Fortunately, another major commodity traded in the area was salt.

Salt is essential for life, for preserving food and for putting on your chips, and it was not in great supply in West Africa, where the heat also meant it was even more important for a body to survive.

If you live on the coast, you can get salt by evaporating seawater to create sea salt – but this does not travel or keep well, so wasn’t very helpful if you lived far from the coast.

Another alternative was to make salt by deriving it. You can do that by burning plants such as millet and filtering the ash to derive salts what is known as salt ash or pot ash.

But, better than both of these is rock salt, also known as Halite. This occurs where you get something like a dried out lake bed or one-time ocean floor.
The salt is evaporated from the water as the area dries out and becomes a layer in the ground. This layer gets overlaid by further sediment deposited on it and over time it gets compressed and hard and dense to the point where it is basically a rock – rock salt.

Rock salt is great for people because it doesn’t absorb water like sea salt, so it keeps better, it can be just dug up out of the ground, so is relatively easy to get hold of if you’ve got the deposits, and you can chop out handy slabs of the stuff, and shape them nicely ready for easy transportation.

This was all so handy, it was also very, very valuable.

And so, although our mind leaps to gold when we think of the trans Saharan trade, we can also thank a humble rock – rock salt - for the prosperity of the Ghana empire. In particular, the salt mines of Idjil in the Sahara were a famous source of the salt for the Ghana Empire.

Idjil is located in Mauritania, and Mauritania is the Westernmost country in Africa that also happens to be on the Tropic of Cancer.

So now we’ve met our first rock, and found our starting place, now it’s time to try to travel as far as we can following the Tropic of Cancer, until we find our hard place.

Travelling the Tropic of Cancer

And we’ve already met our first traveller, the Arab geographer, historian and ancient travel blogger named al Masudi.

Al Masudi was born in Baghdad about 896CE, qualifying him for our time period, although not much is known about his early years. He is said to be a descendant of Prophet Muhammed's friend, Abdullah Ibn Masud.

His Wikipedia has him down as a Historian, Geographer and traveller, which must look great on a business card. He wrote a number of books, up to 35 or so, of which the most famous is Meadows of Gold.

This isa mix of history, comparative anthropology and travel guide and one of the things that makes Al Masudi is notable in his interest in countries and cultures outside of Islam.

To write all this, whilst he did use other sources, he also travelled extensively, and is believed to have personally Syria, Iran, Armenia, the the Indus valley, Sri Lanka, Oman, and the east coast of Africa.

He explains in his own writings the importance of this personal experience and adds “The information we have gathered here is the fruit of long years of research and painful efforts of our voyages and journeys across the East and the West, and of the various nations that lie beyond the regions of Islam.”

He also says ““The author of this work compares himself to a man, who having found pearls of all kinds and colours and gathers them together into a necklace of and makes them into an ornament that its possessor guards with great care.”

Now he didn’t go to West Africa himself, although it is thought he made it to East Africa, but as we mentioned he does write about West Africa and it is very clear it was possible to travel from West Africa on the gold-salt trade routes and get yourself to the Persian gulf.

So Al Masudi gets us from Mauritania, West Africa, easily to Arabia and there he actually introduces us to our next traveller.

In the introduction to one translation of Meadows and Gold, the authors claim that Al Masadi met another traveller and historian, a man named Abu Zaid al-Sirafi on the coast of the Persian Gulf.

And Abu Zayd Al-Sirafi can pick us up in the gulf, and take us all the way to China.

Abu Zayd Al Sirafi is, like Al Masudi a traveller and a historian and an author. Also like Al Masudi not a great deal is known about him, but he is believed to be from or connected to the city of Siraf, a port in Iran that was part of a trade route to India, giving him the opportunity to travel.

He wrote the second half of a book called Accounts of India and China which is a book of travellers tales.

It’s not a long book, nor does it even really have a narrative structure. It is an almost random set of histories, tales and cultural observations, about both India and China but also other middle Eastern locations.

But we’re trying to travel as far as we can along the Tropic of Cancer and China is about as east as we can get, so I’ll give you a couple of examples of what Al Sirafi has to say about China.

About promiscuous women: “Among the Chinese there are certain women who do not wish to be virtuously married but prefer a life of sexual promiscuity. The practice is for such a woman to go to the office of the chief of police and declare her renunciation of the married life and that she wishes to be entered into the list of harlots.”

She then gets given a necklace with a copper tag by way of identication and pays a yearly sum for what I can only describe as her harlot’s license.

Apparently this deal is pretty serious, because the penalty for marrying one of these women is death.

Once properly licensed and with up to date paperwork, these women then, according to Al Sirafi, “go to wanton and licentious foreigners who have arrived in the land and also to the Chinese themselves, spending the night with them and leaving the following morning.”
So having piqued our interest, he just suddenly jump topics, in this case, moving straight onto his next section, entitled ‘Chinese Copper coinage.

Some of the sections are more self-serving than other, such as “crops, warriors and the awe in which Arabs are held” but mostly it’s just interested observations, such as:

“On the subject of eunuch slaves… they function as overseers of taxes and as doorkeepers of the treasury. Some of them are of non-Chinese origin, captured in the borderlands, then castrated; others come from the native Chinese population and are castrated by their fathers, then presented by them to the ruler as a means of gaining favour.”

When they go out, “they are preceded by men with wooden instruments like clappers; when they beat them, the sound can be heard from far away, and none of the populace remains on any part of the road along which the slave or the ruler intends to pass… Thus not a single one of the common people is to be found along their route.”

Al Sifari also brings us this short and sweet tale: “All the kings of India and China believe in the transmigration of souls and hold it as an article of faith. A trustworthy informant reported that one of their kings in these lands was afflicted by smallpox. When he had recovered, he looked in the mirror and thought how hideous his face had become. Seeing one of his brother’s sons, he said to him, “it is not for the like of me to dwell in this body, now it is so changed. The body is, after all, a mere receptacle for the soul; when the soul passes out of it, it returns in another receptacle. You must be king in my place, for I shall now disjoin my soul from my body, until such time as I alight in another’s body’ He then called for a dagger of his that had a particularly sharp edge, and commanded that his head be severed with it. He was duly decapitated, then his corpse was burned.”

The end.

How about the Chinese manner of urination?

“They urinate from a standing position…. The rulers themselves, the army commanders and the other people of high rank use tubes of lacquered wood, each a cubit in length and with a hole at either end, the upper one big enough for the user to insert the head of his penis; when he wants to urinate, he stands on his feet, aims the tube away from himself and urinates through it. They maintain that this method is healthier for their bodies.”

He can also be critical, saying “The Chinese are unhygienic and they do not wash their backsides with water after defecating but merely wipe themselves with Chinese paper.”

But a major thing that Al Sirafi starts his half of the book with is about how China has changed especially relating to trade. He says: “the situation has changed, in China in particular… The reason for the deterioration of law and order in China, and for the end of the China trading voyages from Siraf, was an uprising led by a rebel from outside the ruling dynasty known as Huang Chao.”

“At the outset of his career he had been involved in armed banditry and hooliganism, causing general mayhem and attracting a rabble of witless followers.”

His warriors go on a bit of a rampage, destroying towns and, of particular interest to our trader, “Huang Chao also cut down all the trees in Khanfu, including all the mulberry trees; we single out mulberry trees for mention because the Chinese use their leaves as fodder for silkworms, owing to the destruction of the trees, the silkworms perished and this, in turn, caused silk, in particular, to disappear from Arab lands.”

So you can see he’s really interested in the trade impact of these events.

He goes on to say, “Huang Chaom marched on one city after another, laying waste to each.”

So Al Sirafi has brought us all the way to China, which is also on the tropic of Cancer and he has introduced us to an interesting character who appears to have rebelled against the soft government who were making China a hard place for the people to live

The story of Huang Chao

In 835CE which was during the Tang dynasty in China, a man named Huang Chao was born
He was well educated, but he failed his civil-service examinations.

In fact, according to Wikipedia “It was said that Huang was capable in swordsmanship, riding, and archery, and was somewhat capable in writing and rhetoric.” which reads like an end-of-term report card at pirate college.

Having failed his exams Huang had to find another way to make his living. Fortunately for the symmetry of this episode, he became a salt smuggler.

Salt was a government monopoly, and so was very expensive. In fact, monopolising salt was just one of the ways that the government had been making life difficult for the people

So, it is perhaps not surprising when a rebellion broke out.

In fact, a number of rebellions broke out, including one by another salt smuggler in 874 which Huang joined. This started out ok, but ended with the rebel forces being divided, half of them went off to do their own thing, under the leadership of Huang Chao.

So, as described by Al Sirafi, he does indeed go on something of a rampage.

His forces pushed into the south and in 879 take the rich trade city of Guangzhou. He then moves into the Lingnan region, where he doesn’t do so well. In fact, he loses about 40% of his forces to illness and the enemy starts to close in.

Starting to get a bit desperate, Huang decides to try to bribe his way out. He sends. an enemy leader named Zhang a bunch of gold and he writes letters to Zhang’s boss Gao offering to give up if they can give him a good deal.
Gao senses his enemy is weak, and decides that not only is he about to beat Huang, but he wants to get all the credit, so he sends home additional troops that had been provided to help him in his battle with Huang.

This proved to be something of a mistake, as Huang then broke off negotiations, set out with his troops to battle Zhang and he beat him decisively. in 880ce Zhang was defeated and he was killed in the battle into the bargain.


Huang goes on to attack and capture the Tang capital of Chang'an, partly with the help of some of the Tang dynasty soldiers themselves who were fed up they kept seeing new soldiers arrive with better equipment than they had, so when they camea across Huang, they acted as guides for him instead of fighting.

In 881 Huang Chao having taken the capital declares himself the Emperor of Qi. And asks the Tang generals to recognise him.

Unfortunately, they do not.

In 883 the Tang forces, assisted by a group of nomadic Turkish tribes, drove Huang out of the capital.

And it got worse, Imperial troops caught up with Huang as he was crossing the Yellow River and inflicted a heavy defeat on his forces.

Now there were enemies all around Huang, he was you might say between a rock and a hard place. There were more battles and more losses until eventually, in July of 884CE, Huang and his family were killed, or some say Huang committed suicide, but either way, it brought the Huang rebellion to a final end.

But, it was hardly victory for the Tang dynasty either. Their authority had been successfully challenged, more rebellions were inevitable.

In fact, the Dynasty would last only another twenty years. In 907 the Tang dynasty was brought to an end by Zhu Wen, who was himself, one of the generals who had taken part in the rebellion and fought under Huang Chao.

And what of his legacy – was he a hero or villain of history. Well Chiang Kai-Shek called him one of ‘the two most notorious brigands in Chinese history’ and the Communist party of China called him an “early champion of the rights of the masses” so, you decide.

What is clear is that with the hardship of a failing dynasty, and the disruption of a decade of violent rebellion, China at the end of the 9th century was difficult, you might even say, a hard place.

And so Ryan that is our journey, from a rock in the form of Salt, dug out of the ground in slabs in Mauritania, across the Sahara desert, heading East to the ports of Saudi Arabia and Oman, until we reach the coast of India and on to the far East of a China, where we find a land in uproar and turmoil.

In other words, we’ve travelled between a rock and a hard place, along the Tropic of Cancer, in the 9th century,

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