在中世纪后期，人们习惯用磨料刮去羊皮纸的表面，把纸上的所有文字都擦得干干净净。
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.
第四章考察西欧中世纪后期知识传播的媒介，分别讨论口语媒介与文字媒介在知识传播过程中的作用。
The Fourth Chapter surveys the media of Western Europe in the late Middle Ages by which knowledge was communicated and discusses the roles of the oral media and written media.
在艺术与人文，在即将到来的削减将是最具破坏性的，不再有市场的图书模仿中世纪的论文，更多的脚注不是文字。
In the arts and humanities, where looming cutbacks will be most devastating, there is no longer a market for books modeled on the medieval dissertation, with more footnotes than text.
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