Bess and George could have shouted with excitement but they kept still and followed the straight-backed woman with the uptilted head. She led the girls through a section filled with figures of knights in armor and deadly swords.

"Ugh! I don't like this room," Bess whispered. "It's too scary."

"That is too bad," said Miss Wilkin. "Brave men fighting for their countries used these weapons."

Presently they came to the most unusual exhibit the girls had ever seen. Enlarged gla.s.s eyes hung on all the walls. In display cases beneath them were pictures of fish, animals, and humans, with descriptions of their types of eyes.

"Look!" said George. "This caption says a housefly has a compound eye with four thousand lenses."

"No wonder he's hard to catch," Nancy remarked.

Just then all the lights went out. The room was in complete darkness, but in a moment a reddish light began to appear high on the rear wall.

Seconds later it became a fiery, glowing eye!

CHAPTER IV.

Fiery Red Hair

FOR several seconds Nancy, Bess, and George stood transfixed by the awesome sight of the glowing eye. At times it blinked and seemed to grow redder.

Bess grabbed Nancy's hand. "What is it?" she whispered tensely.

"I don't know."

"Let's get out of here," Bess pleaded. "This place gives me the creeps."

"Not yet," Nancy answered. "I want to see what happens."

The words were barely said when the glowing eye disappeared. There was pitch blackness for several seconds, then the ceiling lights came on. Nancy turned to ask Miss Wilkin for an explanation.

She had vanished!

"Where did she go and why?" George asked. "She's a strange person."

Bess and George started for the entrance, but Nancy paused to look closely at the spot where the glowing eye had appeared. Though the wall was of wood and paneled in large squares, there was no visible opening or sliding section near the glowing eye. Nancy found a high stool and set it under the panel where the glowing eye had shone. She stood on the stool but was unable to move the panel. And the wood was not hot!

Nancy was sure no image of the eye had been projected onto the wall.

"There must be a cold light behind this panel," she said to herself. "A very bright heat-less light."

Her friends had come back. "Learn anything?" George asked.

"No," Nancy replied. "It's a puzzle."

The girls found Miss Wilkin at her desk in the entrance hall. She still had the same expressionless look and offered no explanation of what had happened. Nancy asked her for one.

The woman answered stiffly, "I left to see why the lights went out."

"And the glowing eye?" Nancy prodded.

"That," Miss Wilkin replied, "is used by the engineering students at Emerson who come here to attend lectures given by our member scientists."

"And are the students supposed to give an explanation of the glowing eye?" Nancy asked.

"Yes, but so far none of them has."

The woman stood up and escorted the visitors to the front door. She seemed eager to have them leave.

Nancy smiled and said, "May we come again sometime and see more of the exhibits?"

"If you wish," Miss Wilkin replied, but there was no cordiality in her voice.

The girls drove off, discussing the strange adventure.

"Do you suppose," George asked, "that Ned is connected with this glowing eye bit?"

"Perhaps," Nancy replied. "He's in the engineering school. But I'm surprised that he didn't mention it when I told him about the glowing eye."

"I'm not." George smiled. "Maybe he thought he could find a solution on his own," she teased.

Nancy said, "Ned may have figured out the secret of the glowing eye and been kidnapped because of his discovery."

"That could connect the kidnappers with the Anderson Museum," George commented.

"Maybe in a roundabout way," Nancy replied. To herself she was saying, "I wonder how much Marty King knows about this."

Bess, silent until now, said, "I didn't like that Miss Wilkin and I wouldn't trust her the length of this car. She's spooky and I'll bet she knows a lot more than she's telling."

"I'm inclined to agree," said Nancy. "Let's stop at the library and see what we can find out about the Anderson Museum."

The girl at the reference desk there told them she had never been to the museum but understood it was a spooky place. "But look in the newspaper file. I think there's an article in one of the papers."

Nancy's search was not particularly rewarding. She learned that a large fund had been left to the museum as an endowment to take care of it for educational purposes. There was no mention of a glowing eye.

"Perhaps Burt and Dave will know something about it," George suggested.

Nancy drove directly to the Omega Chi Epsilon fraternity house. Burt and Dave had just come in and greeted the girls warmly. Burt was a rather stocky, athletic blond boy; Dave was slender and blond. They played on the college football team with Ned.

"Any news of Ned?" Nancy asked immediately.

"Not a word," Burt replied. "But Dave and I tracked down a bit of information that might link a certain man with Ned's disappearance."

"Tell me about him," Nancy begged.

Burt said that in one of Ned's engineering courses there was a graduate student with fiery red hair who worked next to Ned in the lab. "He disappeared at the same time Ned did."