Throckmorton’s Sign
Sears and Zemansky's University Physics by Young and Freedman (12th edition) features some intriguing practice problems in it. Upon first glance, the problems seemed no stranger then those in my high school physics textbook (the author had a bit of a penguin fetish) but Young and Freedman's continual reference to a hypothetical cousin "Throckmorton" piqued my interest.
On page 197 of volume one of University Physics we find the following example problem:
At a family picnic you are appointed to push your obnoxious cousin Throckmorton in a swing. His weight is w ... you push Throcky...
...the second approach is far easier in this situation because Throcky...
Now, the first time I saw the name Throckmorton, I just thought that it was a funny name. But the authors keep using the name throughout the book, numerous times.
On page 495, we find the following problem on mechanical waves:
Your cousin Throckmorton is playing with the clothesline.
...write equations for the displacement as a function of time of Throckmorton's end of the clothesline...
I know that there are several more places in the previous chapters that reference "your cousin Throckmorton," but I really don't feel like scanning through several hundred pages just to find references to Throckmorton.
Eventually, I looked up the name Throckmorton, and found out that according to "Who Named It," Throckmorton's sign is "the position of the penis in relation to unilateral disease."
I can just imagine the authors of the book giggling like little school boys when they wrote these problems...