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They established themselves in the stables building of the mansion, soon dubbed 'the Cottage', and developed the ideas that the Poles had supplied at the eleventh hour.
他们在庄园的马房里工作，后来把这里取绰号叫"村头"，他们在此研究波兰在那天11点时提供的资料。
There was no glamour about ciphers. In 1939 the job of any cipher clerk, although not without skill, was dull and monotonous.
密码本身没有什么乐趣，在1939年，密码工作是非常枯燥乏味的，但它是无线电通信的必要环节。
But ciphering was the necessary consequence of radio communication.
无线电广泛用于空、海、和机动的陆地工事。
Radio had to be used for aerial, naval, and mobile land warfare, and a radio message to one was a message to all.
一个无线电信息发射出去，可以被所有方向接收，所以必须对信息进行加密。
So messages had to be disguised, and not just this or that 'secret message', as with spies and smugglers, but the whole communication system.
不光是间谍或其它机密信息需要加密，整个通信系统的所有信息都需要加密。
It meant mistakes, restrictions, and hours of laborious work on each message, but there was no choice.
这就意味着漏洞和限制，还有极大的工作量，但是他们别无选择。
The ciphers used in the 1930s did not depend on any great mathematical sophistication, but on the simple ideas of adding on and substituting.
30年代的密码技术并不依赖数学技巧，只是一些基本的叠加和替换。
The 'adding on' idea was hardly new; Julius Caesar had concealed his communications from the Gauls by a process of adding on three to each letter, so that an A became D, a B became an E, and so on.
叠加并不是个新颖的想法，朱利叶斯·凯撒就通过把字母叠加3位，使A变成D、B变成E等等，使他的通信无法被高卢人理解。
More precisely, this kind of adding was what mathematicians called 'modular' addition, or addition without carrying, because it meant Y becoming B, Z becoming C, as though the letters were arranged around a circle.
准确地说，这种叠加就是数学上讲的模加，也就是无进位加法，因为它将Y变成B、Z变成C，就好比把字母排成了一个圆圈。
Two thousand years later, the idea of modular addition by a fixed number would hardly be adequate, but there was nothing out-of-date about the general idea.
在凯撒时代远去2000年之后，固定数字的模加，已经很难满足需要了，但这个基本思路并没过时。
