Music like 40 Winks

To take forty winks is to take a nap for a short period of time (usually not in bed), or to take a short sleep during the day. Related idiomatic sayings such as could not sleep a wink provide the mental picture of a wink being the shortest type of sleep available and "forty winks" therefore gives an indication of an appropriate short sleep.

To emphasize that forty winks was a nap not taken in a bed, Lewis Carroll used the idiom in his novel Sylvie and Bruno when the main protagonist is constantly nudged by the Master of Ceremonies who is saying, I can't let you sleep here! You're not in bed, you know!; he replies, I know I’m not, I’m in an arm-chair, whereupon the Master says, Well, forty winks will do you no harm and walks off.