“That would burn your skin as quick as pure agenothree,” he exclaimed. “Based on that solution, too. Now, observe. These tubs contain blocks of metal, one each of zinc and copper, in a watered solution of sulfuric acid which makes the metal dissolve in such a way that a chemical reaction occurs. This gives us a form of activity I have called chemical reaction energy. The c.r. produced can be controlled at this point,” and he ran a finger down the metal arm which was poised over an expanse of thin grayish material, attached at both ends to rollers. The Smith turned a knob. The pots began to bubble gently. He tapped the arm and a series of red marks of different lengths began to appear on the material which wound slowly forward. “See, this is a message. The Harper adapted and expanded his drum code, a different sequence and length of lines for every sound. A little practice and you can read them as easily as written words.”

“I do not see the advantage of writing a message here,” and F’lar pointed to the roll, “when you say…”

The Smith beamed expansively. “Ah, but as I write with this needle, another needle at the Masterminer’s in Crom or at the Crafthall at Igen repeats the line simultaneously.”

“That would be faster than dragon flight,” Lessa whispered, awed. “What do these lines say? Where did they go?” She inadvertently touched the material with her finger, snatching it back for a quick examination. There was no mark on her finger but a blotch of red appeared on the paper.

The Smith chuckled raspingly.

“No harm in that stuff. It merely reacts to the acidity of your skin.”

F’lar laughed. “Proof of your disposition, my dear!”

“Put your finger there and see what occurs,” Lessa ordered with a flash of her eyes.

“It would be the same,” the Smith remarked didactically. “The roll is made of a natural substance, litmus, found in Igen, Keroon and Tillek. We have always used it to check the acidity of the earth or solutions. As the chemical reaction energy is acid, naturally the litmus changes color when the needle touches its surface, thus making the message for us to read.”

“Didn’t you say something about having to lay wire? Explain.”

The Smith lifted a coil of fine wire which was hooked into the contraption. It ran out the window to a stone post. Now F’lar and Lessa noticed that posts were laid in a line marching toward the distant mountains, and, one assumed, the Masterminer in Crom Hold.

“This connects the c.r. distance-writer here with the one at Crom. That other goes to Igen. I can send messages to either Crom or Igen, or both, by adjusting this dial.”

“To which did you send that?” Lessa asked, pointing to the lines.