where the
staple of the soil came from there, and that I was right in saying that
there were atoms of lava in every Scotch boy's broth. Not that there
were ever (as far as I know) volcanos in Scotland or in England. Madam
How has more than one string to her bow, or two strings either; so when
she pours out her lavas, she does not always pour them out in the open
air. Sometimes she pours them out at the bottom of the sea, as she did
in the north of Ireland and the south-west of Scotland, when she made the
Giant's Causeway, and Fingal's Cave in Staffa too, at the bottom of the
old chalk ocean, ages and ages since. Sometimes she squirts them out
between the layers of rock, or into cracks which the earthquakes have
made, in what are called trap dykes, of which there are plenty to be seen
in Scotland, and in Wales likewise. And then she lifts the earth up from
the bottom of the sea, and sets the rain to wash away all the soft rocks,
till the hard lava stands out in great hills upon the surface of the
ground. Then the rain begins eating away those lava-hills likewise, and
manuring the earth with them; and wherever those lava-hills stand up,
whether great or small, there is pretty sure to be rich land around them.
If you look at the Geological Map of England and Ireland, and the red
spots upon it, which will show you where those old lavas are, you will
see how much of them there is in England, at the Lizard Point in
Cornwall, and how much more in Scotland and the north of Ireland. In
South Devon, in Shropshire--with its beautiful Wrekin, and Caradoc, and
Lawley--in Wales, round Snowdon (where some of the soil is very rich),
and, above all, in the Lowlands of Scotland, you see these red marks,
showing the old lavas, which are always fertile, except the poor old
granite, which is of little use save to cut into building stone, because
it is too full of quartz--that is, flint.

Think of this the next time you go through Scotland in the railway,
especially when you get near Edinburgh. As you run through the Lothians,
with their noble crops of corn, and roots, and grasses--and their great
homesteads, each with its engine chimney, which makes steam do the work
of men--you will see rising out of the plain, hills of dark rock,
sometimes in single knobs, like Berwick Law or Stirling Crag--sometimes
in noble ranges, like Arthur's Seat, or the Sidlaws, or the Ochils. Think
what these black bare lumps of whinstone are, and what th