A moment or two later Sypher was admitted, by the orthodox avenues, into the room.  He looked around him, his hands on his hips.

“I wonder what on earth this would have been like if our dear lady hadn’t had a hand in it.”

As Septimus’s imagination was entirely scientific he could furnish no solution to the problem.  He drew a chair to the fire and bade his guest sit down, and handed him a box of cigars which also housed a pair of compasses, some stamps, and a collar stud.  Sypher selected and lit a cigar, but declined the chair for the moment.

“You don’t mind my looking you up?  I told you yesterday I would do it, but you’re such a curious creature there’s no knowing at what hour you can receive visitors.  Mrs. Middlemist told me you were generally in to lunch at half-past four in the morning.  Hello, an invention?”

“Yes,” said Septimus.

Sypher pored over the diagram.  “What on earth is it all about?”

“It’s to prevent people getting killed in railway collisions,” replied Septimus.  “You see, the idea is that every compartment should consist of an outer shell and an inner case in which passengers sit.  The roof is like a lid.  When there’s a collision this series of levers is set in motion, and at once the inner case is lifted through the roof and the people are out of the direct concussion.  I haven’t quite worked it out yet,” he added, passing his hand through his hair.  “You see, the same thing might happen when they’re just coupling some more carriages on to a train at rest, which would be irritating to the passengers.”

“Very,” said Sypher, drily.  “It would also come rather expensive, wouldn’t it?”

“How could expense be an object when there are human lives to be saved?”

“I think, my friend Dix,” said Sypher, “you took the wrong turning in the Milky Way before you were born.  You were destined for a more enlightened planet.  If they won’t pay thirteen pence halfpenny for Sypher’s Cure, how can you expect them to pay millions for your inventions?  That Cure—­but I’m not going to talk about it.  Mrs. Middlemist’s orders.  I’m here for a rest.  What are these?  Proofs?  Writing a novel?”

He held up the bundle with one of his kindly smiles and one of his swift glances at Septimus.

“It’s my book on guns.”

“Can I look?”

“Certainly.”

Sypher straightened out the bundle—­it was in page-proof—­and read the title: 

“A Theoretical Treatise on the Construction of Guns of Large Caliber.  By Septimus Dix, M.A.”  He looked through the pages.  “This seems like sense, but there are text-books, aren’t there, giving all this information?”

“No,” said Septimus modestly.  “It begins where the text-books leave off.  The guns I describe have never been cast.”

“Where on earth do you get your knowledge of artillery?”

Septimus dreamed through the mists of memory.