This week, Collected Wisdom is writing a song. It's going to be an anthemic evocation of a changing world. We've already got the first line: "Come gather 'round people, wherever you roam." Hmm, sounds a bit familiar. Maybe we should a-change that.
THE QUESTION: Mark Chynoweth, who's currently working in Beijing, says he was recently struck by the title of Bob Dylan's song The Times They Are A-Changin'. He asks: "Is there some vestigial grammar construct or idiomatic phrasing, or even poetical metre that allows us to say things like a-changin'?"
THE ANSWER: The "a" in a-changin' stems from early Middle English and is a reduced form of the preposition "on," writes Laurel Brinton of the department of English at the University of British Columbia in Vancouver. Thus, "he is on changing" would have meant something like "he is in the process of or in the midst of changing."
"This construction," she writes, "is assumed to be one of the sources for the English progressive construction ('He is changing'), which is now the obligatory way we express events that are ongoing or in progress." She says the "a-" form was retained in traditional ballads, and in later texts it provided poets - such as Dylan - with a convenient extra syllable "if such was needed for the purposes of metre."
Ryan Whyte of Toronto says the "a-" prefix endures in nursery rhymes and folk lyrics as well as some dialects. It's an intensifier that emphasizes the verb and is often used in poems and songs to produce a marching or rolling rhythm, as in "A-hunting we will go, a-hunting we will go."
He concludes that Dylan used it to prevent the stressed words "are" and "changing" from "a-clunking."
THE QUESTION: Jonathan Haldane of Mississauga says his five-year-old son, Aidan, stumped him with this query. If fire needs oxygen to burn, and there is no oxygen in space, how is the sun able to burn?
THE ANSWER: Fire on Earth occurs because of a chemical reaction called combustion, writes Peter A. Lewis-Watts of Barrie, Ont. "Combustion requires three components: a fuel source (e.g. wood) plus oxygen, plus a source of energy (e.g. a match). If any one of the three things is missing, combustion won't take place."
The sun, however, is not a ball of fire. He says it "burns" because of a process called nuclear fusion, which occurs where incredibly high temperatures and pressures exist (such as in the core of the sun).
Lionel Shaul of Toronto says that in the sun's interior, hydrogen atoms are continually fusing to produce helium atoms, thereby "releasing great quantities of light and heat as mass gets converted to energy."
Christine Clement of Toronto adds that astronomers estimate the sun to have enough hydrogen to keep it going for five billion years.
- How far can a fly fly before it gets tired and has to take a break? Emily Tousaw of Ottawa wants to know.
- David Brooks of Toronto asks: How are new signs for sign language determined? Is there a council that decides, for instance, what the signs for "tweet" or "blog" are?
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