“I know,” cried Vane—“convection: it has to do with water expanding and rising when it is hot and descending when it is cold.”
“Of course it has,” said the visitor, laughing, “why you were lecturing me just now on the art of heating greenhouses by hot-water circulating through pipes; well, what makes it circulate?”
“The heat.”
“Of course, by the law of convection.”
Vane rubbed one ear.
“You had not thought of that?”
“No.”
“Ah, well, you will not forget it again. But, as I was saying—suppose I wanted to try and perform a simple experiment to prove, on a small scale, that the pipes you are designing would heat. I cannot see the things I want, and I’ll be bound to say you have them somewhere here.”
“Oh, yes: I’ve got them all somewhere.”
“Exactly. Take my advice, then, and be a little orderly. I don’t mean be a slave to order. You understand?”