It was noted here recently that several readers complained that this newspaper's diet experts had mistakenly defined the word "calorie." The experts said it was the amount of heat needed to raise the temperature of a liter of water by one degree, but the readers said it was the amount of heat needed to raise the temperature of a gram of water one degree.

In dealing with the matter, I pointed out that when "calorie" is spelled with a lower-case "c," it is called a gram calorie or small calorie; when it is spelled with a capital "C," it is sometimes called a kilocalorie, kilogram calorie or large calorie, and it refers to a liter of water.

Julian V. Noble of Charlottesville has now added to my education by informing me: "The common unit of measurement in nutrition is the Calorie (which is 1,000 calories). Since a liter of water weighs (under appropriate conditions of temperature and pressure) 1,000 grams, the definition which appeared in the nutritionists' article was a correct one, except for the lack of capitalization."

The Britannica bears him out, and I must admit that it was news to me that nutritionists who write "calories" mean "Calories." I didn't realize that when they say there are 150 calories in a bottle of beer they mean 150 kilocalories, or roughly enough energy to bring two quarts of water to a boil from room temperature. Yikes!

Incidentally, Noble added this comment in his letter: "Frankly, if you would like to concern yourself with the problem of proofreading at The Washington Post, it would be more appropriate to worry about the frequently misspelled words, the often appalling grammar, the misplaced or incomplete sentences, the lost paragraphs, and the repeats which make the news articles such lively reading."

Alas, yes. Everybody on duty grabs a first edition hot off the presses each night in a team effort to search out and correct errors, but we always miss some. Errors, I fear, will never become an endangered species until man himself is extinct.