Monday, May 07, 2007

Why is it "two shakes of a lamb's tail"? Wouldn't "one shake" be faster?

Who's asking: Paul Guyot, St. Louis, MO

This question revealed a major gap in my circle of acquaintances: I don't know any sheep farmers. I was going to seek some out, but that will take a while, and I'm traveling too much this month.

So here's my usual combination of online research and making stuff up.

First off, some people say "three shakes" instead of "two shakes." Three shakes? That's just silly. Avoid these people, along with people who say "between you and I," "utilize," and "to be honest with you..."

No one seems to know where the phrase comes from, but people generally agree that lambs can shake their tails pretty fast, making two shakes almost as fast as one shake -- so perhaps the implication is that the listener needs to be a little patient, but not very. The tone of it is always vaguely apologetic; we use it to refer to ourselves, and you'd never hear anyone ask for something to be done in two shakes of a lamb's tail.

What's very cool and unexpected is that "shake" has become an official time measurement in nuclear science. Nuclear engineers and astrophysicists use "shake" to mean 10 nanoseconds. (A nanosecond is 10 to the power of negative nine; 10 nanoseconds is ten to the power of negative eight. Admiral Grace Hopper, whom I had the honor to meet on two occasions, used to hand out lengths of wire just under a foot long, which demonstrated the distance light travels in a nanosecond.)

As for how fast I can shake my tail -- well, never mind. Momentum can be a frightening phenomenon.

5 comments:

Anonymous said...

My favorite ovine-centeric (ovinic?) turn of phrase is "As well for a sheep ..." This is a shortened version of "May as well hang for sheep as for a lamb" -- either animal in question being stolen, of course.

Use it ruefully, but also to allow yourself to get away with big errors in judgment. After all, who wants small regrets?

-- Ed

Anonymous said...

My math teacher always uses this phrase and no one had ever heard it before so when we heard him say it we all laughed. I mean who wouldn't laugh hearing this for the first time. I absolutely love it because it is out there and I don't think I would hear someone use this phrase in a serious manner.

HsuedM said...

Hi,
Maybe its written two because a slight gap comes between the two shakes. And in my opinion, those seconds represent the real meaning of the idiom.

David Baril said...

The notion of a shake being the interval between two shakes got me thinking... wouldn't a "shake" imply at least two movements of the tail, one each in opposite directions? Hence two shakes would mean four "wags" if we take that to mean a single movement of the tail in one direction. We could then argue that the traditional "two shakes" is in fact redundant. Does anyone have any idea of how fast a lamb's tail shakes? My guess is that it would be at least 250 milliseconds (1/4 of a second) - nowhere near 10 nanoseconds. But perhaps "two shakes" is not far off "just a sec"! :-) David Baril, Almonte ON

Anonymous said...

"Three shakes" is U.K. usage; "two shakes" is more general U.S. usage.

From a British website discussing the U.K./U.S. difference:

My knowledge of Econ is deep,
The rate that you quote is too steep.
The dollar, I've found
Is two to the pound.
Not 3-to-2 shakes, as in sheep.

http://www.phrases.org.uk/bulletin_board/50/messages/177.html

--Beth P.