Southern Sweden, early spring, as the country emerges from another long, dark, and cold winter. With this climate its no surprise that the Swedes are pioneers of instant light and heat. This is the Swedish Match Industrys factory near Tidaholm. The Tidaholm factory churns out 250 million matches a day for export to 80 countries.

Every match starts life as a chunk of wood. A match that bends when you try to strike it would be useless, so they use hard 1)aspen wood to make rigid matchsticks.

Each log will become nearly 400,000 matches, enough to last the average Swede a thousand years. The problem is the logs are covered in soft 2)fibrous bark thats not stiff enough for making matches, so theyre fed into the stripping machine, which ruthlessly grinds away the bark. But the bare logs are still three meters long; too big for the processing machines. A circular saw makes short work of them, slicing the trunks into uniform 60 centimeter-long chunks called “3)billets.” If you tried chopping these chunks of hard wood into matches, youd be at it all year. So, instead of slicing the wood, they peal it with a specialist machine called a “rotary 4)lathe.” One by one the spinning logs are forced onto a blade which shaves them into sheets called “5)veneers,” just one matchstick thick. Veneers that pass 6)muster pile up against this unique machine. It chops the stack into 15 million tiny sticks or “splints” an hour.

The strangest thing about matchsticks is that theyve got to burn well when you need them to burn, and theyve got to go out and stay out when youve finished with them. So Thorsten Hobst pours flame 7)retardant 8)monoammonium phosphate into a giant blender. Here its mixed with water, then piped into these revolving chambers to soak the splints.

Thorsten makes sure theyve been properly dried out. He checks the woods humidity level is below 5%. Then he needs to see that the flame retardant is doing its job. As the wood burns the monoammonium phosphate in this five gram pile of matchsticks expands and chars. This stops the match burning any more once the flame is out. Hes hoping to see just 9)nought point six of a gram of ash remaining. Any less and the matches kept on 10)smoldering, but much more and the match hasnt burnt enough. If theyre burning right, the batch is ready to make the transformation from sticks to matchsticks.

This is the incredible continuous machine. Invented 150 years ago, by Swede Alexander Lagermann, this feat of engineering transforms two million splints into 40,000 boxes of matches every hour. With a bit of shaking and shoving each stick is aligned and dropped into holes in this metal conveyor belt.

Every match has to burn reliably first time, so first stop on the machine that never stops is the 11)paraffin. But even a stick soaked in paraffin wont just spontaneously 12)combust. Thats where the match head comes in. So over in the batching room Peder Johanssen is busy cooking up a mix to start a fire. A 13)squeegee of 14)gelatin works as glue to hold the burning stuff in place. The business end of the match is made from 15)potassium chlorate, also found in fireworks and gunpowder. This kick starts the burn, setting light to the paraffin in the splint. After a drop of red to make it pretty, the mixture is ready to go to the continuous machine. The splints are dipped in the head mixture 4,000 at a time. The trouble is, if they box them now, the 16)gloopy heads would stick together. This is where the continuous machine comes into its own. More than two thirds of its 150 meter length is actually one giant moving drying rack. For the hour it takes a match to move from dipping to packaging, its just airing.

The safety match was born.

这个国家刚刚走出了一个漫长黑暗的寒冬，我们来到初春的瑞典南部。有这种气候，也难怪瑞典人是瞬时照明与取暖方面的先驱。这是蒂达霍尔姆附近的瑞典火柴厂。蒂达霍尔姆工厂每天大批量制造两亿五千万根火柴，并外销到80个国家。

每根火柴都从大块木头开始。在点火时会弯曲的火柴是没有用的，所以他们用坚硬的山杨木来制造不易弯曲的火柴。

每根圆木都会变成近四十万根火柴，足以让一个瑞典人用上一千年。问题在于包着圆木的是多纤维的软树皮，其硬度不适合做火柴。于是它们被投入剥皮机里，这台机器会毫不留情地磨掉树皮，但剥皮后的圆木依然有三米长，对加工机器来说太大了。一台圆锯迅速地把圆木统一锯成60厘米长的短圆木。如果你要把这些硬木块砍成火柴，你会忙上一整年，所以小圆木不是被直接切片，而是用一种叫旋切机的专门机器进行切割。一条条旋转着的圆木被推到刀片上，刨成只有一根火柴那么厚的薄木片。经检验合格的薄板堆起来，放在这台特殊的机器上，它每小时可将一堆堆的薄板切成1500万根细棒，这些细棒叫“木梗”。

火柴棒最奇异的地方在于当你需要时，它们必须良好燃烧，等你用完时，它们又必须永远熄灭。所以托森·霍布斯特要把阻燃材料磷酸二氢铵倒入一个巨大的搅拌机里，将它与水混合，然后输送到这些旋转室里去浸泡火柴梗。

托森要确认浸泡后的火柴梗确实已经烘干。他检查木头的湿度是否低于5%，然后他要检查阻燃剂是否有效。随着木头燃烧，这堆五克火柴梗里的磷酸二氢铵会膨胀并烧成炭，这样火柴在火焰熄灭后就不会再燃烧。他希望最后只剩下0.6克的灰烬。如果不够这个重量，火柴会继续闷烧；比这重则表示火柴没有烧尽。如果燃烧适当的话，这批材料就准备好要从木棒变成火柴棒了。

这就是不可思议的连续机，150年前由瑞典人亚历山大·拉格曼发明，这个工程设计上的杰作能每小时将200万根木梗变成四万盒火柴。经过机器稍微摇晃推挤，每根火柴都对准并落入这条金属输送带的孔洞里。

每根火柴第一次划着时都要可靠地一次便烧起来，所以在这台永不停止的机器上的第一站是石蜡。但就算是浸了石蜡的木棒也不会自己点燃。那就该火柴头出场了。在配料室里，佩德·约翰森正忙着配制可燃的混合物，其中的明胶是粘着剂，其作用是固定燃烧物。火柴的使用端用氯酸钾做成，它也用于制造烟火和火药。它会启动燃烧，点燃木梗上的石蜡。在加了一点起装饰作用的红色后，混合料就可以送入连续机了。一次会有四千根木梗一起被浸入火柴头混料里。问题是，如果现在火柴就装盒，湿粘的火柴头会粘在一起。这就是连续机发挥作用的时候了。机器150米长，其中三分之二以上的部分其实是一个巨大的移动干燥架。火柴从浸沾到包装所需的一个小时，都只是在风干。

安全火柴就这样诞生了。