"I see! Splendid! Down comes the rain and puts out the fire! But will the shower last long enough?"
"Really, I'm surprised at you, Tom! The fall from a tank like that will be equivalent to an average week's rainfall. But the point of the idea is the composition. I've tried other preparations without success, but this stuff of mine sets hard and yet melts easily. By varying the proportions of the ingredients you can get it to melt at different temperatures, but I haven't quite finished my experiments in that direction. The difficulty is to gauge the exact temperature required, but I'll manage it before long."
"It hasn't been tried yet in a building, then?"
"Not exactly; but a decent local builder was rather taken with it when I showed it to him, and he's giving it a trial at the new Literary Institute he's putting up. The building was stopped by the war, but he has already started work again, and he's willing to test the idea before the plasterers finish. He has rigged up a sort of tray on the laths in the roof of the big room, and one of these days is going to put a brazier underneath. You see, if the stuff melts too easily, it will only mean a slop on the floor, and won't do any damage."
"I see. What are you going to call the stuff?"
"Time enough for that when I've perfected the invention and sent in for my patent. Here's my road-sweeper."
He pointed to a somewhat rusty vehicle standing against one of the walls.
"I'm only waiting for a supply of petrol to try it," he added. "The old engine uses up a frightful lot. But our allowance is due in to-morrow. I say, can you stay a day or two? Mrs. Pouncey can put you up."
"Rather! I've got ten days' leave."
"That's all right, then. Now we had better get back to the garage. Wilkins will be in a bait if it's not open sharp at two."