Teaching reading: Where did the term Skimming (speed reading) derive from?

Skimming is a well-known strategy for speed reading.
Do you have any idea why this technique is called Skimming as opposed to something else? What association you make of the term and the actual strategy?
I want my students to have something to relate the word to so that it’s easier for them to remember it and not confuse it with, say, Scanning or some other strategy.
Your answers will be greatly appreciated. Thanks in advance.