明史·张溥传
张溥抄书

溥幼嗜学。所读书必手钞，抄已朗诵一过，即焚之，又抄，如是者六七始已。右手握管处，指掌成茧。冬日手皲，日沃汤数次，后名读书之斋曰“七录”，以此也。……溥诗文敏捷。四方征索者，不起草，对客挥毫，俄顷立就，以故名高一时。

Since childhood, Zhang Pu had been fond of learning. He always copied with his own hand every book he perused, read it aloud once, and then burned the copy that he had made.What was more, he didn’t stop at making only one copy of a book but made six or seven copies. As a result, thick calluses appeared on his right hand from holding the writing brush.

In winter his hands became chapped and cracked and he soaked them in hot water several times every day. Then he named his study ‘Seven Copies’ meaning just that.

Zhang Pu had a very nimble train of thought when writing, and people came from near and far asking for his poems and prose. Without making a rough sketch he moved his writing brush and finished his works in the visitors’ presence in only a little while. Because of this he enjoyed tremendous popularity for a time.