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Lacking such cathode ray tube storage, he had to plump for the mercury delay lines, not with any great enthusiasm, but because they were already working.
因为没有符合这种要求的阴极射线管存储器，所以图灵只好采用水银延迟线。图灵对水银延迟线并不是很热情，只是因为它们是现成就能用的。
They held the obvious disadvantage, from the point of view of accessibility, of involving a delay.
从可读取性和延迟的角度来看，水银延迟线有明显的劣势。
His plan was for a delay line to hold a sequence of 1024 pulses, so it was like chopping up the 'tape' of the Universal Turing Machine into segments each of 1024 squares in length.
按照图灵的计划，每条延迟线要维持一串1024个脉冲的序列，这就相当于把通用图灵机的纸带分段，每段1024个方格。
It would take an average of 512 units of time to reach a given entry. However, this was an improvement upon the 'papyrus scroll'.
这将花费平均512个单位的访问时间，来读取一个特定的存储项，与埃及沙草纸卷相比，这是很明显的进步。
As for the other most important aspect of the machine, this was the 'Logical Control'. It corresponded to the 'scanner' of the Universal Turing Machine.
另外一个重要的问题就是逻辑控制，相当于通用图灵机的"扫描器"。
The principle was simple: 'The universal machine has only to keep looking at this description'—that is, at the instructions on its tape—'to find out what it should do at each stage.'
它的原理很简单，通用机一直按照描述数，也就是纸带上的指令，来决定每个时刻应该做什么。
So the Logical Control was a piece of electronic hardware which would contain two pieces of information: where it was on the 'tape', and what instruction it had read there.
所以"逻辑控制"就是一个带有两项信息的电子硬件，这两项信息是：它现在位于纸带的什么位置，以及它在那里取到了什么指令。
The instruction would take up thirty-two 'squares' or pulses in a delay line store, and might be of two kinds, in the design that he proposed.
按照图灵的设计，一条指令占32个方格，或者说32个脉冲。
It might simply cause the 'scanner' to go on to another point of the 'tape' for its next instruction.
指令有两种，一种是使扫描器移到某个方格去读下一条指令，
Alternatively, it might prescribe an operation of adding, multiplying, shifting or copying, of numbers stored elsewhere on the 'tape'.
另一种是描述某种操作，比如对某个方格中的数进行加、乘、移位或复制。
In the latter case, the 'scanner' was to move to the next point on the 'tape' for its next instruction.
在第二种情况下，扫描器会自动移到相邻的方格去读取下一条指令。
None of this involved anything but the reading, writing, erasing, changing of state, and moving to left and right,
这些操作只涉及读取、写入、清除、改变方格的状态，以及左右移动扫描器，
that was to be done by the theoretical Universal Turing Machine working on the description numbers on its tape—except that there were special facilities added so that addition and multiplication could be achieved in only a few steps, rather than with thousands of more elementary operations.
这都与理论中的通用图灵机完全一致。唯一的不同就是引入了特殊的计算部件，使加法和乘法可以在几步内完成，而不是几千步。
