"Which means?" asked Ardan.
"It means," said the Captain, now taking part in the discussion, "that the half of v prime squared minus v squared equals gr multiplied by r over x minus one plus m prime over m multiplied by r over d minus x minus r over d minus r ... that is—"
"That is," interrupted Ardan, in a roar of laughter, "x stradlegs on y, making for z and jumping over p! Do you mean to say you understand the terrible jargon, Captain?"
"Nothing is clearer, Ardan."
"You too, Captain! Then of course I must give in gracefully, and declare that the sun at noon-day is not more palpably evident than the sense of Barbican's formula."
"You asked for Algebra, you know," observed Barbican.
"Rock crystal is nothing to it!"
"The fact is, Barbican," said the Captain, who had been looking over the paper, "you have worked the thing out very well. You have the integral equation of the living forces, and I have no doubt it will give us the result sought for."
"Yes, but I should like to understand it, you know," cried Ardan: "I would give ten years of the Captain's life to understand it!"
"Listen then," said Barbican. "Half of v prime squared less v squared, is the formula giving us the half variation of the living force."