Part 3 (1/2)
”A snag in the shape of extra hard rock,” replied the tunnel contractor ”Briefly, Paleozoic rocks make up the eastern part of the Andean Mountains in Peru, while the western range is formed of Mesozoic beds, volcanic ashes and lava of comparatively recent date Near the coast the lower hills are coranite, with, here and there, a strata of sandstone or limestone
These are, undoubtedly, relics of the lower Cretaceous age, and we, or rather, my brother, states that he has found them covered with marine Tertiary deposits
”Now this Mesozoic band varies greatly Porphyritic tuffs and massive limestone compose the western chain of the Andes above Lima, while in the Oroya Valley we find carbonaceous sandstones Soh the Cretaceous period is also largely represented
”Nohile these different h probleer, still we are ured on a certain percentage of them Up to the present time we have met with just about e expected, but e did not expect was so we came upon when the tunnel had been driven three miles into the mountain”
”What did you find?” asked Toy to understand the terms used Mr Damon did not, however, and when Mr
titus rolled off so investor softly murmured such expressions as
”Bless my thermometer! Bless my porous plaster!”
”We found,” resumed Mr titus, ”after we had bored for a considerable distance into the mountain, a mass of volcanic rock which is so hard that our best diamond drills are dulled in a short time, and the explosives we use ive us hardly any progress at all
”It was after several trials, and when ress, co, that he wrote to ht of you, Tom Swift, and your powerful explosive, for I had read about it
”Now then, will you sell us some of your powder--explosive or whatever you call it--Mr Swift, or tell us where we can get it? We need it soon, for we are losing valuable time”
Mr titus paused to draw on a piece of paper a roughconstructed He shohere the two railroad lines were, and where the new route would bring therade up which it would have been iht
”What do you say, Mr Swift?” the contractor concluded ”Will you let us have some of your powder? Or, better still, will you come to Peru yourself? That would suit us iround And you could carry out your plan of going with your friend here,” and Mr titus nodded toward Mr Da”
”Well, I was thinking of it,” Toether that it seems sort of natural for us to 'team it' I have never been to Peru, and I should like to see the country
There is only one h, that bothers me”
”What is it?” asked Mr titus quickly ”If it is a question of overne sum for this tunnel, and we stand to make considerable, even if ere the lowest bidders We can afford to pay you well--that is, we shall be able to if we can co me now--the unexpected strata of hard rock we have met with, which seems impossible to blast But I feel sure we can do it with the explosive used in your giant cannon”
”That is just the point!” Tom exclaimed ”I am not so sure my explosive would do”
”Why not?” the tunnel contractor asked ”It's powerful enough; isn't it?”
”Yes, it is powerful enough, but whether it will have the right effect on volcanic rock is hard to say I should like to see a rock saraph to have soerly ”Meantime, here is a description of it I can read you that”; and, taking a letter froical description of the hard rock
”Hum! Yes,” mused Tom, as he listened ”It seems to be of the nature of obsidian”
”Bless my watch chain!” cried Mr Damon ”What's that?”
”Obsidian is a volcanic rock--a sort of colass and flint for hardness,” Tom explained ”It is brittle, black in color, and the natives of the Ad their spears hich they slay victims for their cannibalistic feasts”
”Bless asped Mr Damon ”Cannibals!”
”Obsidian was also used by the ancient Mexicans to ers,” Tom went on ”When Cortez conquered Mexico he found the priests cutting the hearts frolass-like rock, known as obsidian It may be that your brother has met with a vein of that in the tunnel,” Tom said to the contractor