“New Yorkers are noted for their stupidity” (NYC’s population is very dense)

A popular joke has a teacher ask students what the people of London or New York are noted for. One student says that the people are noted for their stupidity because the textbook says that “the population is very dense.”
 
The joke was told about London in 1910 and about New York City by at least 1925.
 
 
6 June 1910, The Daily Times (New Philadelphia, OH), pg. 2, col. 2:
Dense.
One day the teacher asked her class to write an essay on London, about which they had just been reading. When examining their papers later she was surprised to read the following:
 
“The people of London are noted for their stupidity.”
 
“Where did you get that from?” asked she of Maggie Jones.
 
“Please, miss, it’s all in the book. It says ‘the population of London is very dense.’”—London Answers.
 
16 December 1925, Scranton (PA) Republican, pg. 14, col. 1:
LITTLE BOY (at school): The people of New York are noted for their stupidity.
TEACHER: Wherever did you get that information?
BOY: From the book, miss, It says the population f New York is very dense.—Answers.
 
13 March 1949, Illinois State Journal-Register (Springfield, IL), pg. 44, col. 7:
Teacher: What are the people of New York noted for?
Boy: The people of New York are noted for their stupidity.
Teacher: Where did you get that information?
Boy: From our books, Miss Smith. It says, “The population of New York is very dense.”
—James Paul Kamm, 12, Girard.
 
Google Books
September 1964, Boys’ Life, “Think and Grin,” pg. 74, col. 1:
Teacher: What are the people pf New York noted for?
Student: Their stupidity.
Teacher: Where did you get that idea?
Student: It says in my book that the population of New York is very dense.—Martin Scatola, Yonkers, N.Y.
 
Google Books
June 1966, Boys’ Life, “Think and Grin,” pg. 74, col. 2:
Teacher: What are the people of New York noted for?
Charlie: For their stupidity.
Teacher: Where did you get that idea?
Charlie: It says in my book that the population of New York is very dense.—Timothy Steele, S. Montrose, Pa.
 
Google Books
August 1978, Boys’ Life, “Think & Grin,” pg. 66, col. 3:
Teacher: What are the people of New York noted for?
Tim: For their stupidity.
Teacher: Why, where ever did you get that idea?
Tim: It says right here in this book that the population of New York is very dense.—Dennis Roques, St. Louis, Mo.
 
11 September 1983, Newsday (Long Island, NY), “Smiles,” Kidsday, pg. I7, col. 3:
Teacher: What are the people of New York noted for?
Howie: Their stupidity.
Teacher: Where did yu get an idea like that?
Howie: It says in my book that the population of New York is very dense.
—Laura Bechtle, Rockville Centre