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Tuesday, November 26, 2013

The Bessemer Process, or Give Me Steel


The Bessemer process, devised by Henry Bessemer - a London-born inventor who happened to work in a mint in Paris, before fleeing as the Revolution and the subsequent Terror ravaged la cité - solved a big deal of military problems by devising an efficient way to manufacture steel, in great quantities and in a short time.
Henry Bessemer: such a jolly good fella !

The idea, which probably won't make much sense at a first read, was to simply blow air through molten, dirty iron ore (high phosphorus, silicon, manganese, carbon), in order to get rid of most impurities by oxidizing them. A lot of molten ore. And a lot of molten air. How do you call that ? In a single word, Pyrotechnics

So, he used the excuse of making killing people more economic for Great Britain to invent the most spectacular process in metallurgic industry to his (and possibly our) day. And, incidentally, earn shitloads of money.

So far, so good. But let's tackle the devil: where do you get the ore ? How do you melt it ? How do you blow air through ?

First of all, the raw material for the Bessemer process is pig iron, which is obtained by smelting iron ore. Ok, what does this even mean ?
Iron Pig
Ores are rocks containing a decent amount of some metal one is interested in, together with an awful amount of crap which you will want to get rid of.
Yeah, this iron ore has a lot of iron.

To do this, you need to melt the ore in a furnace.
First of all, a few impurities will get oxidized and fly away, namely carbon and sulphur.
However, the high temperature means that your molten iron will also oxidize like hell, and to fix this you have to introduce some reducing agent, which will efficiently suck oxygen from the iron; the standard way to do this is use carbon, or charcoal, which will produce first carbon monoxide, then dioxide, thus allowing iron to stay classy.
The other problem one has to tackle is the presence of impurities, which will be removed by using an appropriate flux, usually limestone, which absorbs phosphates, and reacts with carbon and sulphur dioxide, thus forming a slag which stays separated from pure iron, while at the same time impeding oxidization of the latter.

The molten iron at this point is not by any means 100% pure; a particular type of furnace, the blast furnace, produces pig iron, in which the carbon content is still relatively high (3.5-4.5%).

Bessemer Converter
So, now you just pour your molten pig ore into your bedroom's Bessemer converter, and start blowing air into the cistern, thus causing flames as high as 15m to be projected high into the atmosphere. Weeeeeeeeee !
What's happening ? Well air is pushing through, and silicon, manganese, carbon are oxidized, either escaping spectacularly as gas, or condensing as dull slag.
The huge flames tell a lot about the current state of the purification process, and they are the main indicator as to the right moment to stop the process.
The molten remains are finally moved to moulds, where slag, being less dense, will float to the top, allowing for an easy removal.
What lies below, then, is iron with the (hopefully) right amount of carbon, a.k.a. steel.

Time to build some serious gun !

Anyway, the Bessemer process has now been superseded by better alternatives, so all you just read is obsolete.

Kisses and hugs !


Also, for a nice, Brit narrated history: http://www.youtube.com/watch?v=qJ3aTpKMmfQ

Also, how does Iron work ?

Wednesday, October 30, 2013

Ahrrrrrrrrr ! Pirates in Cartagena



All of these pirates attacked Cartagena.
Left to right, top to bottom: Francis Drake, Generic Pirate, Giovanni da Verrazzano, Jean François de la Roque de Roberval, John Hawkins, Monkey D. Luffy.

The first pirates to attack the Spanish Empire did so under French Corsair patent: the Italian navigator Bernardo da Verrazzano (a.k.a. Juan Florian, apparently just the same Giovanni da Verrazzano, also Italian, who first explored the lands between Newfoundland and Georgia, and christened the islands now forming the state of Rhode Island - periods of activity are apparently compatible) in 1521 intercepted a Spanish flotilla, en route to Spain with the Monteczuma treasure, and managed to take a considerable part of it back to La Rochelle.
La Rochelle under siege by Richelieu (1627). Probably not its happiest moment.

The first pirate to enter Cartagena, in 1544, was the French aristocrat Robert Ovalle, or Roberto Baal, actually Jean François de la Roque de Roberval, who stole into the city in the early morning of "dia de Santiago" (25 of July), and managed to obtain a ransom of 200k pesos after threatening to burn the city to the ground (Cartago Delenda Est !).
Cartago deleta est. I.e. don't fuck with the Romans.
The French apparently loved the climate in Cartagena (well, try to outlive a winter in Paris..), as in 1559 Martin Coté and his beloved brother Jean de Beautemps attacked head first the city with 1000 something veteran pirates, managed to get control of Getsemanì, a strategically placed island right on the side of the historical centre of Cartagena which just everyone used as a base to force the town to its knees, and forced the town to its knees. Ransom and all. Usual story.
No, not this Gethsemane,
Cunning was the weapon of choice for the 1568 attack by John Hawkins, who placidly attempted to inconspicuously dock in Cartagena with his fleet in order to sack it, as he had done in other Spanish ports of the Caribbeans. Sadly, the governor of Cartagena decided to welcome him with a shower of cannon balls, poison arrows and arquebus shots. Hawkins got away with hide and everything, played the pirate gentleman for a while longer and died off the coast of Puerto Rico twenty seven years later.

After the French and the English, Dutch pirates, which were known as Watergeusen or Zeegeusen - apparently and appendix of the Geuzen movement, a calvinist and aristocratic enterprise which opposed Spanish domination in the Netherlands - began raiding the Caribbean.

The Geusen emblem even has the tetragrammaton on it !
The first pirate age was concluded with Francis Drake's attack on Cartagena in 1586, who began playing the corsair after escaping a great purge of pirates by the Spanish in 1579 - which he accomplished by sailing beyond Cape Horn and attacking the Spanish colonies on the Pacific - and accomplishing for the second time in history a circumnavigation of the world.
Cartagena went all out to get rid of him, and even the pious Franciscan and Dominican friars took arms to fight the invader, allegedly singing and praying all the time, but Drake, probably annoyed by the constant chanting, was relentless, captured the city, got helluvalot pieces-of-eight as a ransom, and was gone in a cloud of dust. Or a spray of surf. Choose your own adventure !

While Drake's life was by no means a dry one, he died of dysentery in 1596.

Francis in Cartagena. He managed a 500+k pieces-of-eight ransom. Pas mal.
(P.S.: Other pirates did follow ! However, I'm lazy)

Friday, October 25, 2013

From Palomino to Cabo de la Vela. Guajira. Colombia

20/10/2013

Map !!


Palomino-Riohacha

Planning the next steps with my favorite travel companion
Buses apparently do not comply with the highest standards in Guajira, which entails that, en route from Palomino to Riohacha,
1) I didn't succumb to the soft embrace of a freezing death
2) my back was constantly being beaten by a few hard parts of my seat, which were made to stick out by an evil maker.
Just a few soldiers were scattered patrolling the road, probably protecting the gentle white pearl of Riohacha by the growing threat of barren soil and diminishing vegetation.

Ah, Riohacha ! Shining medallion of gold in the East, gate to fabulous riches, ward of the pyramids so many weary travelers have spotted, glimmering on the horizon in the middle of the desert heat.

Yes, a sultry, bleak town with little to offer but transportation and lousy food (truth be said, the area by the coast is not so horrible, but I need to keep complaints frequent for some inexplicable internal urge).

Riohacha-Uribia

Cootrauri (calle 15 @ 5-39, as per instructions from Lonely Planet - from the bus terminal, just follow calle 15 in the direction you came from, second the left-right bend, cross the road and you'll find it on your right. Looks a little sketchy, but it actually isn't) quickly provided me with a 4x4, a pilot, three silent fellow travelers, probably shocked by my gulping unreasonable amounts of beer at 10am (wtf, it was hot !), and some 20 minutes wait in which I was lucky enough to see the final scenes of Face/Off: John Travolta, Nicholas Cage, tawdry camera movement and slow motion, cheesy lines, horrible plot. Fuck you IMDB.

In the end, the road to Uribia proved exceptionally smooth, as it was an almost empty, largish asphalt road which stretches from Riohacha all the way to Maicao and beyond, into the Venezuelan territory. It was also decently kept, so that we didn't really need all our 4x4 power. But we would. Soon ..

Closing in toward Uribia, the vegetation grows scarcer, while more and more cacti decide to exploit the thin awning provided by sad looking local trees, just a hue away from dusty green, well far from the lush colors of tropical forests.

The town is quite ugly, but the market area is teeming with life: everyone has apparently a share in the trades, everyone's buying and selling. I guess that one huge achievement of modern distribution systems is to get rid of the redundant intermediaries (which are therefore free to dedicate themselves to more productive activities - such as a PhD in physics ?)

Here my westerness/europeanness/whiteness was inevitably spotted, and truck drivers tried to exploit my innocence and kind heart (heart begins with a "ha!" sound) by trying to extort 30k COP for a ride to Cabo de la Vela. Sensing - with a broken "Ha!"rt - an attempt of ass-fucking, I politely (but not so much) flipped the bird, disembarked and boarded a different truck.

The truck was a pick-up (take this, make everything old and rusty) to which someone had added a metal structure, for overhead luggage room, and a few benches, and then decided to cram as many people as would fit (something like this). In our specific case, we had a few guys hanging on the metal structure (quite outside the enclosed part), suckling babies, aguardiente addicts, and a tied-up goat, whose bleats are positively akin to babies'.

No information on the goat's fate has ever reached me. My guess.

Uribia-Cabo de la Vela

And, finally, we hit the road !

And what a road: an unpaved, dusty carretera extends into the desert, cutting through the scant vegetation of cacti, pools of water the color of mud, trees so thirsty you feel like watering them is your sacred duty, sparse flocks of handfuls of goats. The road unchanging, unbending for hundreds of miles (about 40 actually, all the way to Puerto Bolìvar), running parallel to train tracks apparently only worthy of transporting wares (btw, whom do they belong to ? Multinationals working in the Guajira ? Yes, apparently it's the Cerrejón, which mines thermal carbon). Oh, right: a few wagons lie warped and broken by the tracks, sad mementos of a dateless bombing. Well it could be this bombing (October 13, 2013!), while this happened right after I got back from Cabo de la Vela (October 23, 2013). Authorities suggest that this kind of bombing is FARC's doing.

After about one hour on this stretch of road, things got dire: we turned left, into some godforsaken, mud-encrusted track, elegantly waving amidst the dusty cacti-and-trees condos; the apparent thirst of the road was quenched by countless pools - formed by either lluvia or evil-minded gods - interrupting the track,
Our engine failed, in no particular order, in the middle of these lagoon sized ponds, a few meters after passing them, right before the crossing, and also on completely dry ground. Just about everywhere.
I'm pretty sure big G is saturating the colors..
Just as the dust on clothes, hands, head, lungs becomes almost unbearable, the Caribbean Sea suddenly opens up on the horizon, and the wind blows strong and sweet, making the sun of the early afternoon a trifle to withstand. Or Burn, Baby, Burn.
I survived
Windsurf
As I learned from one of my fellow truck-travelers, a kite surf school has opened - and is rolling - in Cabo de la Vela. I couldn't really find online info about them. Windsurf is actually the only thing you can do in Cabo de la Vela, and the spot is just Perfect: absolutely flat sea, with no waves at all, while a strong wind is always blowing outwards. I'm still wondering how that's possible. In particular considering that I was suffering from otitis at the time.
Tours
Apparently, at least a couple of places in the pueblo (all along the sea) offer tours to Punta Gallinas directly from Cabo de la Vela. I didn't inquire as to the prices, however, as my interest was thwarted by the sudden realization that 1) there was no ATM in the village, and 2) I had a grand total of about 70k COP, which needed to cover for all my expenses for two days - lodging included. Shit.
Lodging
I stayed at Jarrinapi, which offers cabanas for 35k (private restroom) or amacas for 10k. Due to my funding problem, I took a hammock: power is available, but restrooms were quite dirty, the lack of non-dusty surfaces is kinda annoying,  and there is no running water: baldes y pozos - ay carajo !

The Village (horror vibe intentional)

Cabo de la Vela is evidently a fishermen's village (no sails though, it's all so engine operated - sigh), and no other activity whatsoever is apparent; the unreasonable amount of "restaurante y hospedaje"s hints at a lively high season, as does this flyer I found, hanging on the wall outside a random tiendita.
Oh, right, fuck their (somewhat appropriately) goddamn christian radio blabbering in the background. It was even worse than Radio Maria.
Highlights:
"Peddlers must not exist, if they are there they must be located in a specific place" (...)
"Collaborate on the measures to be taken about the sale of hallucinogens"
"The sale of dusts is completely forbidden"
I guess they must have fun !
As I ended up there in Extremely Low Season, I was surrounded by Wayuu: I asked "Wayuu here ?", and they would reply "Wayuu here ?".
...
Yes it's a pun. No they don't speak English. My jokes are wasted on you people. (Hint: Wayuu is pronounced as in "Why you")
Hello Polly !
The only other Westerner - as inappropriate as the noun is - was Nunu, a Portuguese now probably in Venezuela, or Rio, or Portugal. As he's an architect, we sat staring at local cactus-made cabanas, reverse engineering the construction technique. I think I got it.

So did the night descend. And I wasn't ready. Not at all. A mix of heat, cold, mosquitoes, ear pain made me hope desperately for dawn. Which did come, in the end, opening to a new glorious day of dusty empty roads, glaring locals and little desayuno. (As a side note, the second night was way better, as I had found the One Secret to be able to sleep on hammocks without mosquito nets: just cover every fucking inch of your body, and stop breathing for good measure. Scientific literature states that bugs start feasting on corpses from the second day on.)

Sightseeing

After waking up and downing a poor excuse for a breakfast (pina, 2 maracuyas and a beer), and killing time until 2 (what the hell did I do ?? Oh right, I took a shower .. Technology FTW !), I finally decided to go explore the coast, as Lonely Planet promised me

  1. A Lighthouse !!!!
  2. A wonderful bathing spot of crystal blue water called Ojo de Agua
  3. A blissful orange beach known as El Pilon de Azucar (The sugar heap)
So, after trudging my way up a hill, well into the first hour of walking, I was faced with a handsome promontory featuring a tiny islet, apparently uninhabitable and uninhabited, and a minuscule version of the tour Eiffel, sporting a light at its very top. DEFINITELY not worth it.

The querido Ojo de Agua was a likewise waste of time (a small beach enclosed in rock walls, neither high nor remarkable in any way), and trusted information mongers revealed that Pilòn de Azùcar is more remarkable for its general lack of hygiene and abundance of glass shards than its wonderful colors. All in all, Meh !


Last positive note: I  spent my last for an effin good whole jarrona (some kind of fish?), with a decent amount of vegetables to round things up.

Fuck Yeah !

So, after a better night, blessed by an abating otitis and better anti-mosquito tactics, I was finally able to get back to civilization.

Wednesday, September 25, 2013

Harvard - Hårvård


Harvard ?

When you live a sizable slice of your life in Cambridge, you immediately associate Harvard to its red shield with Truth embroidered on it.



Incidentally, it also makes you think of the MIT logo:
"Mens et manus". Mind and hand. In a mostly male den of engineers. Yes. It's exactly as you're thinking.

Uttering the single word "Harvard" elicits supreme thoughts of great science everywhere in the world.

Everywhere but in Sweden.

In Stockholm:



So much for higher thoughts: Hårvård stands for hair care.

In hindsight, it's no surprise that I never met any Swede in Cambridge.


Monday, September 23, 2013

Stockholm and the grumpy dessert



Gräddbollar


Real life is work in progress. Fuck far field.

Walking in Gamla Stan, surrounded by camera wielding tourists, relaxed Swedes, Shoppes of every shape and content, you're bound to have a close encounter with a Gräddboll.
These guys go by many names - Wikipedia knows them all http://sv.wikipedia.org/wiki/Skumboll.
Emperor Palpatine as he personally endorses Gräddbollar.

Typically Swedish (in Austria they're also known as Schweden Bomben, and Emperor Palpatine apparently also reveres them), and originally from Denmark, at least according to the Israeli newspaper Jerusalem Post, Gräddbollar have succeeded at filling the empty spots inside the arteries of many dwellers of Scandinavia.

At least according to my first-hand research - conducted at Some unnamed café - they are made of an outer well-tempered chocolatey shell which hides a soft MARSHMALLOW CREAM - yes, you read it right, purely deadly sin - and with a thin yet heartening layer of marzipan at the base.
While Grädd is the Swedish for cream, the version I sampled had no hint of ever seeing any.


All my first-hand information was acquired by cajoling a Russian waitress to talk about a Swedish dessert which was prepared according to a Danish recipe.

Oh, by the way, the Gräddboll I sampled was quite horrible.

Of course, this is quite untrue.