After 50 days of gluttony
在长达五十天的暴饮暴食之后
they've grown 10 thousand times heavier
他们增重至幼虫体重的一万倍
But this stage
然而这个时期
25 percent of their body mass is made up of silk glands
丝腺占了体重的四分之一
In the process of turning into adult moths
在转化成蛾的过程中
they spin a cocoon from a single strand of silk
他们从一条丝开始吐丝成茧
which can be over a thousand meters long
丝长甚至超过千米
It was the legendary strength and brightness of silk fibers
丝质纤维因其超凡韧性和艳丽色泽
that made it so sought-after
而广受欢迎
For over 5000 years,
五千多年来
people built great fortunes and mighty kingdoms
人们在纤莹的丝线上编织出巨大的财富
on these delicate threads.
和强大的帝国
And the desert routes those antient traders took
古代商人在沙漠中留下的行商路线
became the fabled Silk Road
成就“丝绸之路”的伟大传说
The principle of extracting raw silk hasn't changed
从生丝中缫丝的原理自发现伊始
since it's discovered
就一直未变
Harvested cocoons are droped into boiling water
将收获的茧倒入沸水中
which unravels the long filaments
使细长的丝茧散释开来
These are then gathered and spun into raw silk thread
然后将之收集起来纺成生丝线