yellowed by time, and apparently torn out of an old copy book.
On this paper was written a single sentence, thus worded:

"It is useless for the engineer James Starr to trouble himself,
Simon Ford's letter being now without object."

No signature.
CHAPTER II ON THE ROAD

THE course of James Starr's ideas was abruptly stopped,
when he got this second letter contradicting the first.

"What does this mean?" said he to himself. He took up the torn envelope,
and examined it. Like the other, it bore the Aberfoyle postmark.

It had therefore come from the same part of the county of Stirling.
The old miner had evidently not written it. But, no less evidently,

the author of this second letter knew the overman's secret,
since it expresslycontradicted the invitation to the engineer to go

to the Yarrow shaft.
Was it really true that the first communication was now without object?

Did someone wish to prevent James Starr from troubling himself either
uselessly or otherwise? Might there not be rather a malevolent intention

to thwart Ford's plans?
This was the conclusion at which James Starr arrived,

after maturereflection. The contradiction" target="_blank" title="n.矛盾；反驳；抵触">contradiction which existed
between the two letters only wrought in him a more keen

desire to visit the Dochart pit. And besides, if after all it was
a hoax, it was well worth while to prove it. Starr also thought it

wiser to give more credence to the first letter than to the second;
that is to say, to the request of such a man as Simon Ford,

rather than to the warning of his anonymouscontradictor.
"Indeed," said he, "the fact of anyone endeavoring to influence my

resolution, shows that Ford's communication must be of great importance.
To-morrow, at the appointed time, I shall be at the rendezvous."

In the evening, Starr made his preparations for departure.
As it might happen that his absence would be prolonged for some days,

he wrote to Sir W. Elphiston, President of the Royal Institution,
that he should be unable to be present at the next meeting

of the Society. He also wrote to excuse himself from two
or three engagements which he had made for the week.

Then, having ordered his servant to pack a traveling bag,
he went to bed, more excited than the affair perhaps warranted.

The next day, at five o'clock, James Starr jumped out of bed,
dressed himself warmly, for a cold rain was falling, and left his

house in the Canongate, to go to Granton Pier to catch the steamer,
which in three hours would take him up the Forth as far as Stirling.

For the first time in his life, perhaps, in passing along the Canongate,
he did NOT TURN TO LOOK AT HOLYROOD, the palace of the former

sovereigns of Scotland. He did not notice the sentinels who stood
before its gateways, dressed in the uniform of their Highland regiment,

tartan kilt, plaid and sporran complete. His whole thought was to reach
Callander where Harry Ford was supposedly awaiting him.

The better to understand this narrative, it will be as well to hear
a few words on the origin of coal. During the geological epoch,

when the terrestrial spheroid was still in course of formation,
a thick atmosphere surrounded it, saturated with watery vapors,

and copiously impregnated with carbonic" target="_blank" title="a.(含)碳的">carbonic acid. The vapors gradually
condensed in diluvial rains, which fell as if they had leapt

from the necks of thousands of millions of seltzer water bottles.
This liquid, loaded with carbonic" target="_blank" title="a.(含)碳的">carbonic acid, rushed in torrents over

a deep soft soil, subject to sudden or slow alterations of
form, and maintained in its semi-fluid state as much by the heat

of the sun as by the fires of the interior mass. The internal
heat had not as yet been collected in the center of the globe.

The terrestrial crust, thin and incompletely hardened, allowed it
to spread through its pores. This caused a peculiar form of vegetation,

such as is probably produced on the surface of the inferior planets,
Venus or Mercury, which revolve nearer than our earth around

the radiant sun of our system.
The soil of the continents was covered with immense forests.

Carbonic acid, so suitable for the development of the vegetable
kingdom, abounded. The feet of these trees were drowned in a sort

of immenselagoon, kept continually full by currents of fresh
and salt waters. They eagerly assimilated to themselves the carbon

which they, little by little, extracted from the atmosphere,
as yet unfit for the function of life, and it may be said

that they were destined to store it, in the form of coal,
in the very bowels of the earth.

It was the earthquake period, caused by internal convulsions,
which suddenly modified the unsettled features of the

terrestrial surface. Here, an intumescence which was to become
a mountain, there, an abyss which was to be filled with an ocean

or a sea. There, whole forests sunk through the earth's crust,
below the unfixed strata, either until they found a resting-place,

such as the primitive bed of granitic rock, or, settling together
in a heap, they formed a solid mass.

As the waters were contained in no bed, and were spread over every
part of the globe, they rushed where they liked, tearing from

the scarcely-formed rocks material with which to compose schists,
sandstones, and limestones. This the roving waves bore over

the submerged and now peaty forests, and deposited above them
the elements of rocks which were to superpose the coal strata.

In course of time, periods of which include millions of years,
these earths hardened in layers, and enclosed under a thick

carapace of pudding-stone, schist, compact or friable sandstone,
gravel and stones, the whole of the massive forests.

And what went on in this gigantic crucible, where all this
vegetable matter had accumulated, sunk to various depths?

A regular chemical operation, a sort of distillation.
All the carbon contained in these vegetables had agglomerated,

and little by little coal was forming under the double influence
of enormouspressure and the high temperature maintained by

the internal fires, at this time so close to it.
Thus there was one kingdom substituted for another in this

slow but irresistiblereaction. The vegetable was transformed
into a mineral. Plants which had lived the vegeta-tive

life in all the vigor of first creation became petrified.
Some of the substances enclosed in this vast herbal left their

impression on the other more rapidly mineralized products,
which pressed them as an hydraulic press of incalculable power

would have done.
Thus also shells, zoophytes, star-fish, polypi, spirifores, even fish

and lizards brought by the water, left on the yet soft coal their
exact likeness, "admirably taken off."

Pressure seems to have played a considerable part in the formation
of carboniferous strata. In fact, it is to its degree of power that

are due the different sorts of coal, of which industry makes use.
Thus in the lowest layers of the coal ground appears the anthracite,

which, being almost destitute of volatile matter, contains the greatest
quantity of carbon. In the higher beds are found, on the contrary,

lignite and fossil wood, substances in which the quantity of carbon
is infinitely less. Between these two beds, according to the degree

of pressure to which they have been subjected, are found veins
of graphite and rich or poor coal. It may be asserted that it is

for want of sufficient pressure that beds of peaty bog have not been
completely changed into coal. So then, the origin of coal mines,

in whatever part of the globe they have been discovered, is this:
the absorption through the terrestrial crust of the great forests

of the geological period; then, the mineralization of the vegetables
obtained in the course of time, under the influence of pressure and heat,

and under the action of carbonic" target="_blank" title="a.(含)碳的">carbonic acid.
Now, at the time when the events related" target="_blank" title="a.叙述的；有联系的">related in this story took place,

some of the most important mines of the Scottish coal beds had
been exhausted by too rapid working. In the region which extends