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Listen to part of a lecture from a Botany class.
聽一段來自植物學課堂的講座。
Hi, everyone.
大家好。
Good to see you all today.
很高興，看到大家都來了。
Actually, I expected the population to be a lot lower today.
實際上，我還以為今天來聽課的人會比上次少很多。
It typically runs between 50 and 60 percent on the day the research paper is due.
一般說來，從研究論文那天開始上課人數的流失率會在 50%到 60%。
Um, I was hoping to have your exams back today, but, uh, the situation was that I went away for the weekend,
嗯，我原來有望今天帶來你們的考試結果，但是，嗯，情況是這樣的，我上周末不在，
and I was supposed to get in yesterday at five, and I expected to fully complete all the exams by midnight or so,
原本打算昨天 5 點到，趕在午夜我平時休息的時間全部完成批改，
which is the time that I usually go to bed, but my flight was delayed, and I ended up not getting in until one o'clock in the morning.
但是我的航班延誤了，直到凌晨 1 點鐘才到。
Anyway, I'll do my best to have them finished by the next time we meet.
不管怎么說，我會盡力在下節課前完成。
OK.
好了。
In the last class, we started talking about useful plant fibers.
在上一節課，我們開始探討有用的植物纖維。
In particular, we talked about cotton fibers, which we said were very useful, not only in the textile industry,
特別是，我們討論了一些棉纖維，我們說過它們很有用，不僅在紡織業來說，在化工業也是如此，
but also in the chemical industry, and in the production of many products, such as plastics, paper, explosives, and so on.
甚至在很多產品中的成果方面，比如塑料、紙、炸藥等等。
Today we'll continue talking about useful fibers, and we'll begin with a fiber that's commonly known as" Manila hemp.
今天我們繼續討論有用纖維，我們將從大家熟知的“馬尼拉麻”開始。
" Now, for some strange reason, many people believe that Manila hemp is a hemp plant.
如今，因為某種奇怪的原因，很多人認為馬尼拉麻是一種麻類植物。
But Manila hemp is not really hemp.
但是馬尼拉麻并不是麻類植物。
It's actually a member of the banana family - it even bears little banana shaped fruits.
它實際上是香蕉科里的一種——它甚至生產形狀跟香蕉類似的水果。
The" Manila" part of the name makes sense, because Manila hemp is produced chiefly in the Philippine Islands and,
這名字中的“馬尼拉”倒是說得過去，因為馬尼拉麻主要產于菲律賓群島，
of course, the capital city of the Philippines is Manila.
當然，菲律賓的首都是馬尼拉。
Now, as fibers go, Manila hemp fibers are very long.
現在，隨著人們對纖維的經營開發，馬尼拉麻纖維變得很長。
They can easily be several feet in length and they're also very strong, very flexible.
它們很容易達到幾英尺長，同時很牢固，柔韌性也很好。
They have one more characteristic that's very important, and that is that they are exceptionally resistant to salt water.
它們還有一個重要的特征，這正是它們對咸水有極強的抗腐蝕性的原因。
And this combination of characteristics long, strong, flexible, resistant to salt water makes Manila hemp a great material for ropes,
正是這些長、堅韌、牢固、抗腐蝕性特征的組合讓馬尼拉麻成為絕好的繩索，
especially for ropes that are going to be used on ocean going ships.
特別是用在遠洋船只上。
In fact, by the early 1940s, even though steel cables were available, most ships in the United States Navy were not moored with steel cables; they were moored with Manila hemp ropes.
事實上，在 20 世紀 40 年代初期，盡管能買到鋼絲繩，但是美國海軍絕大多數的船停泊時用的不是鋼絲繩，這些船用的是馬尼拉麻繩。
Now, why was that?
為什么會這樣呢？
Well, the main reason was that steel cables degrade very, very quickly in contact with salt water.
主要的原因是鋼絲繩接觸咸水后很容易腐蝕。
If you've ever been to San Francisco, you know that the Golden Gate Bridge is red.
如果你去過舊金山的話，你會發現金門大橋是紅色的。
And it's red because of the zinc paint that goes on those stainless steel cables.
紅的原因是因為鋅顏料在鋼索上起作用。
That, if they start at one end of the bridge and they work to the other end,
如果工人們從一頭安裝鋼索到另外一頭，
by the time they finish, it's already time to go back and start painting the beginning of the bridge again,
到他們完工的時候，就該回來重新油漆一遍了，
because the bridge was built with steel cables, and steel cables can not take the salt air unless they're treated repeatedly with a zinc based paint.
因為金門大橋是由鋼絲建成的，同時鋼絲在咸性的空氣中容易腐蝕，除非反復給鋼絲涂上鋅顏料。
On the other hand, plant products like Manila hemp, you can drag through the ocean for weeks on end.
但是，像馬尼拉麻這樣的植物產品，你可以拖著它們穿過海洋好幾個禮拜。
If you wanna tie your anchor to it and drop it right into the ocean, that's no problem,
如果你想綁上錨，然后將錨扔到海里，一點問題都沒有，
because plant fibers can stand up for months, even years, in direct contact with salt water.
因為植物纖維能堅持好幾個月，甚至好幾年，直接與咸水接觸的話。
OK.
好的。
So how do you take plant fibers that individually you could break with your hands and turn them into a rope that's strong enough to moor a ship that weighs thousands of tons?
那么你是怎么將用手可以拉斷的植物纖維做成強韌到可以泊上萬噸船的繩子的？
Well, what you do is you extract these long fibers from the Manila hemp plant, and then you take several of these fibers,
你需要做的是從馬尼拉麻里抽出這些長纖維，然后從中拿出幾縷，
and you group them into a bundle, because by grouping the fibers you greatly increase their breaking strength that bundle of fibers is much stronger than any of the individual fibers that compose it.
揉成一根，因為通過這樣揉搓，極大地加強了這些纖維的抗斷強度這一根的強度比起其中的任何一縷纖維都要強得多。
And then you take that bundle of fibers and you twist it a little bit, because by twisting it,
之后，再拿揉搓好的那根纖維捻一下，
you increase its breaking strength even more.
這樣能讓其抗斷強度得到更大的提升。
And then you take several of these little bundles, and you group and twist them into bigger bundles,
再后來，你將揉搓好的這些纖維揉搓和編織成更大的繩子，
which you then group and twist into even bigger bundles, and so on, until eventually, you end up with a very,very strong rope.
如法炮制，直至做出很大的纜繩。
