"It was, countless centuries ago," replied Ranworth.

"It's a mammoth, and a unique specimen at that. Evidently this one has only recently been uncovered by the unusual thawing of the ice. So far as I could see, it was hardly damaged; no wonder you thought it was alive. Others have been discovered in Northern Siberia, but not so well preserved, We must have those tusks if there's time after we've accomplished our mission. One thing is pretty certain; my brother's party did not come this way. They made use of the left-hand pass."

"How do you know that, sir?" asked Guy.

"Because Claude would have discovered the mammoth. He did not, otherwise he would have sent a wireless report of the great discovery to the Royal Society."

"Unless," Guy ventured to remark, "the mammoth has only appeared since your brother's expedition passed."

Before Ranworth could reply, for a difficult piece of ground required careful handling of the steering gear, a dark object rising clearly above the waste of snow attracted his attention. It was a tent made of skins with the fur still adhering to them.

Ordering the motor to be stopped, Ranworth put the balance rudder hard over. For quite ten yards the hard steel ground itself edgewise over the ice before the sleigh came to a standstill. All hands alighted and hurried towards the solitary evidence of human occupation.

Ranworth untied the carefully secured double flaps and entered the tent.

It was deserted, and contained only a pile of fur rugs, neatly folded and corded, and a tin box conspicuously labelled:

"For emergency use only. R.P.E."