“Where did you get this?” he asked.

“That is something I do not care to answer.  I wish to know what it is.  Is it a gem?  If so, what kind?”

He thought a moment and shook his head.

“I thought I knew every gem on earth.  But I don’t.  This is a new one.  It is beautiful—­just a moment.”  He stepped to the door.  In a moment another man stepped in.  The jeweller motioned towards the ring.  The man picked it up and again came the examination.  At last he laid the glass and ring both upon the table.

“What do you make of it, Henry?” asked the jeweller.

“Not me,” answered the second one.  “I never saw one like it.”

It was as Watson had said.  No man had ever identified the jewel.  The two men were puzzled; they were interested.  The jeweller turned to me.

“Would you care to leave it with us for a bit; you have no objection to us taking it out of the ring?”

I had not thought of that.  I had business down the street.  I consulted my watch.

“In half an hour I shall be back.  Will that be enough time?”

“I think so.”

It was an hour before I returned.  The assistant was standing at the door of the office.  He spoke something to the one inside and then made an indication to myself.  He seemed excited; when I came closer I noted that his face was full of wonder.

“We’ve been waiting,” said he.  “We didn’t examine the stone; it wasn’t necessary.  It is truly wonderful.”  He was a short, squat man with a massive forehead.  “Just step inside.”

Inside the office the jeweller was sitting beside a table; he was leaning back in his chair; he had his hands clasped over his stomach.  He was gazing toward the ceiling; his face was a study, full of wonder and speculation.

“Well?” I asked.

For an answer he merely raised his finger, pointed towards the ceiling.

“Up there,” he spoke.  “Your jewel or whatever it is.  A good thing we weren’t in open air.  ’Twould be going yet.”

I looked up.  Sure enough, against the ceiling was the gem.  It was a bit disconcerting, though I will confess that in the first moment I did not catch the full significance.

The jeweller closed one eye and studied first myself and then the beautiful thing against the ceiling.

“What do you make of it?” he asked.

Really I had not made anything; it was a bit of a shock; I hadn’t grasped the full impossibility.  I didn’t answer.

“Don’t you see, Mr. Wendel?  Impossible!  Contrary to nature!  Lighter than air.  We took it out of the ring and it shot out like a bullet.  Thought I’d dropped it.  Began looking on the floor.  Couldn’t find it; looked up and saw Reynolds, here, with his eyes popping out like marbles.  He was looking at the ceiling.”

I thought for a moment.

“Then it is not a gem?”

He shrugged his shoulders.  “Not if I’m a jeweller.  Whoever heard of a stone without weight?  It has no gravity, that is, apparently.  I doubt whether it is a substance.  I don’t know what it is.”