Part 26 (1/2)

”What's the matter with your eyes, Estelle?” asked Paul, as he looked at her. ”Were you working in the studio to-day? I know those lights always affect my sight.”

”Why, no, I wasn't in the studio,” and then Estelle realized why her eyes were so inflamed--it was from crying. She gave Alice a meaning glance, as though to enjoin silence, but she need have had no fears.

Alice would not betray the secret.

The big gun had been mounted on a level piece of land, not far from the hill, and on this plain had been thrown up earthworks behind which the Union forces would take their stand in an effort to reduce the Confederate stronghold.

”They're going to fire!” cried Estelle as they came within sight of the gun, and saw, by the activities of the men about it, that a shot was about to be delivered.

Alice covered her ears with her hands, and Russ and Paul stood on their tiptoes and opened their mouths wide.

”What in the world are they doing that for?” asked Estelle.

”I can't hear a word you say!” called Alice, making her voice loud, to overcome her own hearing handicap.

”There she goes!” cried Russ.

The earth trembled as flames and smoke belched from the muzzle of the cannon, and the girls screamed.

Something black was seen for an instant in the air amid the swirl of smoke, and then another portion of the hill was seen to lift itself up into the air and dirt and stones were scattered about.

”A good shot!” observed Russ, letting himself down off his tiptoes.

”That would make a dandy scene for the film.”

”That's right,” agreed Paul, also letting himself down and closing his opened mouth.

”Why did you do that?” asked Estelle, when the echoes of the firing had died away. ”Why did you stand on your toes, and open your mouths?”

”To lessen the shock to our ear drums,” answered Paul. ”It is the concussion, that is, the rus.h.i.+ng back of air into the vacuum caused by the shot, that does the damage. By opening your mouth you equalize the air pressure on the inside and the outside of your ear drums, just as you do when you go through a river tunnel. When there is a partial vacuum outside your ear, the air inside you presses the drum outward, and by opening your mouth--or by swallowing you make the pressure equal. Sometimes the pressure outside is greater than the pressure inside, and you must also equalize that before you can be comfortable.”

”But that wasn't why you stood on your toes,” Alice said.

”No; we did that to have less surface of our bodies on the ground so the vibration would be less. If one could leap up off the earth at the exact moment a shot was fired it would be much better, but it is hard to jump at the right instant, and standing on one's toes is nearly as good. Then you present only a comparatively small point which the vibrations of the earth, caused by the explosion of the gun, can act upon.”

”That's a good thing to remember,” Estelle said. ”Are they going to fire again?”

”It looks so,” observed Russ. ”But if they knock away too much of the hill there won't be any left for the pictures to-morrow.”

”I believe they want to make the top of the hill flat,” said Paul. ”They are going to have some sort of hand-to-hand fight on it after the Unionists capture it,” he went on. ”I heard Mr. Pertell speaking of it.”

”There goes another!” cried Alice, as she saw the same preparations as before and one man standing near the gun to pull the lanyard, which, by means of a friction tube, exploded the charge.

Once more the projectile shot out and, burying itself in the soft dirt of the hill, threw it up in a shower.

”That'll save me a lot of work!” exclaimed a voice behind the young people, and, turning, they saw Sandy Apgar smiling at them. ”That's a new way of plowing,” he went on. ”It sure does stir up the soil.”

”Won't it spoil your hill?” asked Alice.

”Not so's you could notice it. That hill isn't wuth much as it stands.