In Europe, before the introduction of the mechanical clock, people told time by sun (using, for example, shadow sticks or sun dials) and water clocks. Sun clocks worked, of course, only on clear days; water clocks misbehaved when the temperature fell toward freezing, to say nothing of long-run drift as the result of sedimentation and clogging. Both these devices worked well in sunny climates; but in northern Europe the sun may be hidden by clouds for weeks at a time, while temperatures vary not only seasonally but from day to night.

Medieval Europe gave new importance to reliable time. The Catholic Church had its seven daily prayers, one of which was at night, requiring an alarm arrangement to waken monks before dawn. And then the new cities and towns, squeezed by their walls, had to know and order time in order to organize collective activity and ration space. They set a time to go to sleep. All this was compatible with older devices so long as there was only one authoritative timekeeper; but with urban growth and the multiplication of time signals, discrepancy brought discord and strife. Society needed a more dependable instrument of time measurement and found it in the mechanical clock.

We do not know who invented this machine, or where. It seems to have appeared in Italy and England (perhaps simultaneous invention) between 1275 and 1300. Once known, it spread rapidly, driving out water clocks but not solar dials, which were needed to check the new machines against the timekeeper of last resort. These early versions were rudimentary, inaccurate, and prone to breakdown.

Ironically, the new machine tended to undermine Catholic Church authority. Although church ritual had sustained an interest in timekeeping throughout the centuries of urban collapse that followed the fall of Rome, church time was nature’ s time. Day and night were divided into the same number of parts, so that except at the equinoxes, days and night hours were unequal; and then of course the length of these hours varied with the seasons. But the mechanical clock kept equal hours, and this implied a new time reckoning. The Catholic Church resisted, not coming over to the new hours for about a century. From the start, however, the towns and cities took equal hours as their standard, and the public clocks installed in town halls and market squares became the very symbol of a new, secular municipal authority. Every town wanted one; conquerors seized them as especially precious spoils of war; tourists came to see and hear these machines the way they made pilgrimages to sacred relics.

The clock was the greatest achievement of medieval mechanical ingenuity. Its general accuracy could be checked against easily observed phenomena, like the rising and setting of the sun. The result was relentless pressure to improve technique and design. At every stage, clockmakers led the way to accuracy and precision; they became masters of miniaturization, detectors and correctors of error, searchers for new and better. They were thus the pioneers of mechanical engineering and served as examples and teachers to other branches of engineering.

The clock brought order and control, both collective and personal. Its public display and private possession laid the basis for temporal autonomy: people could now coordinate comings and goings without dictation from above. The clock provided the punctuation marks for group activity, while enabling individuals to order their own work (and that of others) so as to enhance productivity. Indeed, the very notion of productivity is a by-product of the clock: once on can relate performance to uniform time units, work is never the same. One moves from the task-oriented time consciousness of the peasant (working on job after another, as time and light permit) and the time-filling busyness of the domestic servant (who always had something to do) to an effort to maximize product per unit of time.

在欧洲，在机械表被引入以前，人们利用太阳（比如棍子的影子和日晷）和水钟来确定时间。当然，太阳钟只能用于晴天使用，而水钟表在水温下降到冰点时会出错，长期漂浮的东西因为下沉或堵塞而无法工作。这两种仪器在晴天都运行的很好，但北欧，太阳可能会藏在云后长达一周，同时，温度不仅会随季节中变化，也因昼夜而不同。 中世纪欧洲使得可靠的时间变得更重要。天主教堂每天有七次的祷告，有一个是在晚上，它要求设定闹钟以便在破晓前叫醒布道师。另外新的城市和小镇，由于其空间的限制，他们必须要知道并且安排时间去组织集体活动和分配空间。他们设定时间睡觉。所有这些用老的仪器都是可以一致的，只要只有一个权威的时间记录者。但是随着城市的发展和报时信号的倍增，时间错乱导致了不和与争吵。社会需要一个更加可靠的工具去衡量时间，这个仪器就是机械钟表。 我们并不知道是谁发明了这个机器，或者在哪。它好像是出现在意大利或是英国（也许是同时发明的）在1275年到1300之间。一旦被人们所知，它就快速传播并替代了水钟表，但日晷依然存在，用来对照这个新仪器与原来的计时法。早期的版本很原始，不准确且易坏。 讽刺的是，新仪器有破坏天主教堂权威性的倾向。虽然几世纪以来，尽管城市瓦解，罗马没落，但教堂仪式一直保持着对时间记录的兴趣，教堂时间是自然的时间。白天和黑夜被分为均等的部分，所以除去昼夜平分点，白天和黑夜时间是不均等的；当然因此，这些时间的长度也随着季节变化。但是，机械时钟时间间隔相等，这意味着新的时间计算法。天主教会进行反抗，将近一个世纪都不肯转化到新的时间。但一开始，城镇都接受了均等时间作为他们的标准，并且安装公共的时钟在城镇大楼和市场变成了新的世俗市政权威的标志。每个城镇都想要一个；胜利者视它们为珍贵的战利品，在游人去神圣古迹朝圣的路上，他们专程去看并听这些钟表。 钟表是中世纪机械精巧装置的最大成就。它的正确性的可以通过简单地可观察日出日落等常见现象来证明。这样的结果是对技术和设计进步的残酷的压力。在每个阶段，制表人引领者准确与精度，他们成为了微型化的大师，错误的探测器和校正者，更新更好的搜寻者。因此他们是机械工程的先驱，是工程学其它分支的典范和老师。 钟表带来了秩序和控制，既有集体的也有个人的。它的公开展示和私人拥有铺设了短期自治的基础：人们现在可以不用根据上层的命令来调整去留。钟表也为集体活动提供了时间提示，同时使个人能够安排他们自己的工作，以加强生产力。事实上，生产力的准确概念是时钟的副产物，一旦一个人可以将其表现用统一的时间单位衡量，那么工作就永远都不会一样了。人们从农民以任务为导向的工作方式（在时间和光线条件允许的情况下，一件工作接着一件的干）和家奴以时间为导向的工作方式（总有事情做）中转变到了将单位时间的生产量达到最大化的努力中。