Part I
Professor: Now in Europe in the Middle Ages before the invention of printing and the printing press, all books, all manuscripts were hand-made. And the material typically used for the pages was parchment, which is animal skin that’s stretched and dried under tension, so it become s really flat and can be written on.
During the 1400s, when printing was being developed, paper became the predominant material for books in Europe, but prior to that, it was parchment. Parchment is durable, much more so than paper, and it could be reused which came in handy, since it was a costly material and in short supply, so it wasn’t uncommon for the scribes or monks who produced the manuscripts.
它可以重复使用，这很方便，因为它是一种昂贵的材料，而且供应不足，所以对于制作手稿的抄书吏或僧侣来说重复使用羊皮纸的现象并不少见。
1. printing press
a machine that produces books, newspapers, etc. by pressing a surface covered in ink onto paper 印刷机
E.g.: The printing press gave power to a few to change the world for the many.
印刷机赋予少数人为多数人改变世界的力量。
2. parchment |ˈpɑ:tʃmənt|
noun. material made from the skin of a sheep or goat , used in the past for writing on 羊皮纸
E.g.: old manuscripts written on parchment
写在羊皮纸上的古老手稿
3. tension 张力; thrust 推力; friction 摩擦力; drag 阻力; lift 升力; pull 拉力; repulsion 斥力; pressure 压力; buoyancy 浮力; gravity 重力
4. predominant |prɪˈdɒmɪnənt|
adj. having more power or influence than others 占优势的；主导的
E.g.: Amanda's predominant emotion was that of confusion.
阿曼达主要还是感到困惑。
5. durable |ˈdjʊərəbl|
adj. likely to last for a long time without breaking or getting weaker 耐用的；持久的
E.g.: This varnish provides a durable finish.
这种清漆可作耐久的罩面漆。
6. come in handy
if something comes in handy, it is useful in a particular situation 派上用场
E.g.: That key will come in handy if you lock yourself out.
要是你把自己锁在了屋外，那把钥匙就派上用场了。
7. scribe |skraɪb|
noun. a person who made copies of written documents before printing was invented （印刷术发明之前的）抄写员，抄书吏
E.g.: Then certain of the scribes answering said, Master, thou hast well said.
有几个文士说, 夫子, 你说得好。
Part II
Ah, remember before printing, books were made mainly in monasteries. Well, the scribes often recycled the parchment that had been used for earlier manuscripts. They simply erased the ink off the parchment and wrote something new in its place. A manuscript page that was written on, erased and then used again is called a palimpsest.
Palimpsests were created, well…we know about two methods that were used for removing ink from parchment. In the late Middle Ages, it was customary to scrape away the surface of the parchment with an abrasive, which completely wiped out any writing that was there. But earlier in the Middle Ages, the original ink was usually removed by washing the used parchment with milk. That removed the ink. But with the passing of time, the original writing might reappear. In fact, it might reappear to the extent that scholars could make out and even decipher the original text.
抄书吏经常回收再利用那些早期手稿的羊皮纸，他们只是简单地擦掉了羊皮纸上的墨水，再在上面写一些新的东西。
事实上，那些字迹可能会重新出现到学者们可以辨认甚至破译原文的程度。
1. monastery |ˈmɑ:nəsteri|
noun. a building in which monks (= members of a male religious community) live together 隐修院；修道院；寺院
E.g.: In 1857 Mendel started experimenting with peas in his monastery garden.
1857年，孟德尔开始在修道院的菜园里用豌豆做实验。
2. palimpsest |ˈpælɪmpsest|
noun. an ancient document from which some or all of the original text has been removed and replaced by a new text 再生羊皮纸卷，重写羊皮书卷（全部或部分原有文字被刮去，在上面另行书写）
E.g.: All history was a palimpsest, scraped clean and reinscribed exactly as often as was necessary.
历史变成了一张羊皮纸,可以按照需要擦净重写。
3. customary|ˈkʌstəməri|
adj. if sth is customary , it is what people usually do in a particular place or situation 习俗的；习惯的
E.g.: Is it customary to tip hairdressers in this country?
这个国家兴给理发师小费吗？
4. scrape|skreɪp|
verb. to remove sth from a surface by moving sth sharp and hard like a knife across it 刮掉；削去
E.g.: She scraped the mud off her boots.
她刮掉了靴子上的泥。
5. abrasive|əˈbreɪsɪv|
noun. a substance used for cleaning surfaces or for making them smooth （用来擦洗表面或使表面光滑的）磨料;磨蚀剂
E.g.: Avoid abrasives, which can damage the tiles.
避免使用磨蚀剂，以免损坏瓷砖。
6. make out
to manage to see sb/sth or read or hear sth 看清；听清；分清；辨认清楚
E.g.: I could just make out a figure in the darkness.
黑暗中我只认出了一个人的轮廓。
7. decipher|dɪˈsaɪfə(r)|
verb. to succeed in finding the meaning of sth that is difficult to read or understand 破译，辨认（难认、难解的东西）
E.g.: I'm still no closer to deciphering the code.
我还是无法破译该密码。
Part III
Perhaps, the most famous example is the Archimedes' palimpsest. Archimedes lived in Greece around 200 BCE. And as you probably know, he's considered one of the greatest mathematicians who ever lived, even though many of his writings had been lost , including what many now think to be his most important work called The Method.
But in 1998, a book of prayers from the Middle Ages sold in an art auction for a lot of money, more money than anyone would pay for a damaged book from the 12th century. Beautiful or not, why? It had been discovered that the book was a palimpsest, and beneath the surface writing of the manuscript laid, guess what? Mathematical theorems and diagrams from Archimedes.
你可能也知道，他被认为是有史以来最伟大的数学家之一，尽管他的许多著作已经遗失，包括现在许多人认为他最重要的著作《方法》。
1. Archimedes |ˌɑrkəˈmidiz|
noun. Greek mathematician and physicist noted for his work in hydrostatics and mechanics and geometry (287-212 BC) 阿基米德（公元前287年—公元前212年），伟大的古希腊哲学家、百科式科学家、数学家、物理学家、力学家，静态力学和流体静力学的奠基人，并且享有“力学之父”的美称，阿基米德和高斯、牛顿并列为世界三大数学家。阿基米德曾说过：“给我一个支点，我就能撬起整个地球。
2. BCE=before the Common Era 公元前; CE=Common Era 公元; AD=Anno Domini 公元; AH=Anno Hegirae 伊斯兰教纪元，回历; BC=before Christ 公元前
3. prayer |preə(r)|
noun. words which you say to God giving thanks or asking for help 祷告，祈祷（的内容）
E.g.: Their prayers were answered and the child was found safe and well.
他们的祷告应验了：小孩找到了，安然无恙。
4. auction |ˈɔ:kʃn|
noun. a public event at which things are sold to the person who offers the most money for them 拍卖
E.g.: The house is up for auction (=will be sold at an auction) .
这所房子将被拍卖。
5. theorem |ˈθɪərəm|
noun. a rule or principle, especially in mathematics, that can be proved to be true （尤指数学）定理
E.g.: That is the so-called fundamental theorem of algebra .
这就是代数基本定理。
Part IV
Archimedes' writings were originally done on papyrus scrolls. Then in the 10th century, a scribe made a copy on parchment of some of his texts and diagrams including, as it turns out, The Method. This was extremely fortunate, since later on, the original papyrus scrolls disappeared.
About 200 years later in the 12th century, this parchment manuscript became a palimpsest when a scribe used the parchment to make a prayer book. So the pages, the pieces of parchment themselves, had been preserved. But the Archimedes' text was erased and written over, and no one knew it existed.
It wasn't until 1906 that a scholar came across the prayer book in a library and realized it was a palimpsest, and that the underlying layer of texts could only have come from Archimedes. That was when his work The Method was discovered for the first time.
大约在200年后的12世纪，当一名抄书吏用羊皮纸制作祈祷书时，这份羊皮纸手稿就变成了一个重写羊皮卷。
1. papyrus|pəˈpaɪrəs|
noun. papyrus is a type of paper made from papyrus stems that was used in ancient Egypt, Rome, and Greece （古代埃及、罗马和希腊用的）纸莎草纸
E.g.: Woollen cloth and timber were sent to Egypt in exchange for linen or papyrus.
羊毛料和木材送到埃及以换取亚麻布或纸莎草纸。
2. preserve|prɪˈzɜ:v|
verb. to keep sth in its original state in good condition 维持…的原状；保存；保养
E.g.: This vase has been preserved intact.
这个花瓶保存得完好无损。
3. come across
to meet or find sb/sth by chance（偶然）遇见，碰见，发现
E.g.: I came across children sleeping under bridges.
我偶然发现睡在桥下的孩子。
Part V
Um...the palimpsest then went through some more tough times, but eventually it ended up in an art auction where it was bought and then donated to an art museum in Baltimore, for conservation and study. To avoid further damage to the manuscript, the research team at the art museum has had to be extremely selective in the techniques they used to see the original writing.
They've used ultraviolet light and some other techniques, and if you're interested in that sort of thing, you can learn more about it in an art conservation class. But actually, it was a physicist who came up with a method that was a breakthrough. He realized that the iron in the ancient ink would display if it's exposed to a certain X-ray imaging method, and except for small portions of the text that couldn't be deciphered, this technique's been very helpful in seeing Archimedes' texts and drawings through the medieval overwriting.
他发现古代墨水中的铁元素，如果用某种X射线成像方法曝光就会显现出来。
1. tough |tʌf|
adj. having or causing problems or difficulties 艰苦的；艰难的；棘手的
E.g.: She's been having a tough time of it (=a lot of problems) lately.
她最近的日子一直很难熬。
2. conservation |ˌkɒnsəˈveɪʃn|
noun. the official protection of buildings that have historical or artistic importance （官方对历史或艺术建筑的）保护；文物保护
E.g.: Then he began his most famous work, the conservation and rebinding of the Book of Kells.
之后他就开始了他最为出名的工作，即保护并重新装订《凯尔斯书》。
3. selective |sɪˈlektɪv|
adj. tending to be careful about what or who you choose 认真挑选的；严格筛选的
E.g.: You will have to be selective about which information to include in the report.
究竟要把哪些资料收入报告，你得仔细斟酌。
4. ultraviolet 紫外线的; infrared 红外线的; X-ray X射线; gamma ray 伽马射线
5. overwrite |ˌəʊvəˈraɪt|
verb. to replace information on the screen or in a file by putting new information over it 盖写；重写
E.g.: Send or receiving a new snapshot overwrite the previous image.
发送或接收一幅新的快照会覆盖前面的图象。
10个月宝宝每天需要喝多少奶粉？
