“Catch me!  Jump on the rope!” yelled the guide.

Harriet’s quick eyes, now wide open, caught the significance of the scene.  Without an instant’s hesitation she sprang toward Janus, fairly hurling herself upon him.  One hand grabbed a taut rope that was straining with some heavy weight pulling on it at the other end.

Janus sat up as the girl threw her own weight on the line to assist in holding it until the guide should have recovered himself.

“Oh, what has happened?” cried the guardian.

“Some one is over the edge,” answered Harriet almost breathlessly.  “Quick!  Find out who it is.”

“It’s Tommy!” screamed Margery Brown.

Miss Elting sprang toward the edge of the shelf.

“Stop!” thundered the guide.  “Careful!  Don’t rush.  Take it easy.  All the rest of you stay back.  You go cautiously to the edge, Miss Elting, and find out just what shape she’s in.”

Grubb gave his commands in a quick, business-like tone; at the same time he removed his belt and unfastened the girls’ ropes.

Margery began to scream again.  Jane grasped and shook her.

“Stop that!  Tommy’s doing enough howling for the whole party,” she exclaimed.

Tommy’s cries were all-sufficient—­heart-rending, in fact.  Harriet motioned to Jane to come and assist in holding the rope.  Jane responded promptly.

“May I go and help?” questioned Harriet eagerly.

“Yes.  It’s a good idea.  Keep her quiet if you can,” urged Miss Elting.  “She is likely to saw the rope in two at the rate she is floundering about.  I hope her belt is strong enough to hold.”

“Oh my stars, what a mess!” groaned Jane McCarthy.

“It’s worse than that,” answered Janus, but he did not explain just what danger threatened the screaming little girl.

Harriet turned the rope over to her companion and hurried to the edge of the shelf, where she stretched herself on the rock with her head protruding over.  What she saw was an object that resembled a great spider suspended from a silken thread.  The spider was dangling in the air, with arms and legs working frantically.  The poor little spider, in this instance Tommy Thompson, was slowly turning from side to side, clawing frantically at the smooth side of the mountain when her hands got into position where she could touch it.  Miss Elting was trying to soothe her.  Harriet adopted a different policy.

“Tommy!” she cried sharply.

“Oh, thave me!  Thave me!” wailed the little tow-headed girl.

“Do you want to drop clear to the bottom?” demanded Harriet.

“No, oh, no!  Thave me!  I’ll be good.  I’ll—­”

“You’ll be down there in a heap if you don’t stop struggling.  Listen to me!  Are you going to stop that screaming and do something for yourself, or are we to let you hang there until to-morrow morning?” continued Harriet.