“What do you call a tube with a college degree?”/“A graduated cylinder.”

The term “graduated cylinder” is the subject of an obvious joke:
 
Q: What do you call a tube with a college degree?
A: A graduated cylinder.
 
The joke has been cited in print since at least 1998.
 
   
Wikipedia: Graduated cylinder
A graduated cylinder, measuring cylinder or mixing cylinder is a common piece of laboratory equipment used to measure the volume of a liquid. It has a narrow cylindrical shape. Each marked line on the graduated cylinder represents the amount of liquid that has been measured.
   
Google Groups: alt.fan.dragons
A rebirth
.(JavaScript must be enabled to view this email address)
8/27/98
(...)
What do you call a test tube w/ a degree?
A graduated cylinder 😉
 
Google Books
November 2000, Boys’ Life, “THin & Grin,” pg. 65, col. 2:
Slim: What do you call a tube with a degree?
Jim: What?
Slim: A graduated cylinder.
— D. J. Weber, Arlington Heights, Ill.
 
jokesiteexample.com
Category: Humor jokes
Date Added: 11/10/2007
Joke: What do you call a tube with a degree? A graduated cylinder.
 
English, baby!
Some funny RIDDLES. Do u know others?
Tapita
09:08 PM Dec 28 2008
(...)
Q: What do you call a test tube that graduates from high school?
A: A graduated cylinder
Submitted by Margaret Elliott
 
Twitter
Kenton Silverman
‏@Kenton1985
What do you call a tube with a degree? A graduated cylinder.
5:03 PM - 6 Jan 2010
 
Twitter
Bill Helton
‏@7colonel7
Corny joke…What do you call a test tube with a college degree?  A graduated cylinder!          JROTC student told me that one 2da.
4:01 PM - 11 Feb 2010
     
NPR
Two Scientists Walk Into A Bar
APRIL 01, 2011 1:00 PM ET
IRA FLATOW, host:
This is SCIENCE FRIDAY. I’m Ira Flatow.
(...)
FLATOW: What do you call a beaker with a college degree?
 
Mr. GOLDBLATT: A beaker with a college degree? Graduated?
 
FLATOW: A graduated cylinder.
(Soundbite of laughter)
 
Google Books
October 2011, Boys’ Life, “Think & Grin,” pg. 64, col. 3:
Daffynition: Graduated cylinder — An educated can of soup.
Luke Gentle, St. Michael, Minn.
   
Mostly True Stories of K. Renae P.
Ten Terrible Science Jokes
K. RENAE P. April 23, 2015
(...)
3. What kind of cylinder had a college diploma? A graduated cylinder.