When Encyclopaedia Britannica announced last month that it was discontinuing its print editions after 244 years, company executives noted that there were 4,000 sets of the final 32-volume 2010 edition left in a warehouse, the remnants of an old tradition.

Less than three weeks later, the bulk of them are gone.

Eager buyers have rushed to snap up the last printed sets of the encyclopedias, with only 1,000 left to be sold, said Jorge Cauz, the president of Encyclopaedia Britannica, a company based in Chicago.

Before it announced the end of the print edition on March 13, Britannica was selling the encyclopedias at a languid pace of about 60 each week, at a $1,395 price tag. Since then, it has sold about 1,050 each week, or 150 a day, at the same price.

That is in line with an average week’s sales for some of the periods when the company had a fully staffed sales force. The company expects the remaining 1,000 sets to disappear by mid- to late April. (Sales of the print Encyclopaedia Britannica reached their peak in 1990, when 120,000 sets were sold domestically.)

The sales staff has been so overwhelmed by calls that Britannica’s chief marketing officer has been answering phones to help out.

The encyclopedias, which weigh 129 pounds a set, are being bought mostly by individual consumers, people who are calling Britannica and paying in full on their credit cards, the company said.

“When they thought it would be around forever, there was no rush to buy one,” Mr. Cauz said in an e-mail. “But now, suddenly, it’s a scarce item.”

Print encyclopedias have been gradually edged out by online resources, most recently Wikipedia, the free, crowd-sourced encyclopedia that was started 11 years ago.

The Encyclopaedia Britannica was the oldest continuously published encyclopedia in the English language.