"Real evils, mamma!" reiterated Ferdinand; "you do not then think this a real evil?"
"Indeed, my dear, I do not," replied Mrs. Bernard; "on the contrary, I hope, to Edward it will prove a real good; and I am sure you are none of you so selfish as to wish to deprive him of any advantage, merely for the sake of your own gratification."
"Selfish! Oh, no, mamma, indeed we are not selfish," cried all the children at once: "we will convince you we are not, for we will, this minute, leave off grieving for Edward's departure, and teach ourselves to rejoice, and wish him very happy."
Mrs. B. You will do quite right, my dears; and now let us change the subject, for that is the best way to banish your regret.
Ferdinand. I was very much amused yesterday, mamma, with reading the new book you gave me for a prize a little time ago.
Mrs. B. Miss Edgworth's "Early Lessons," do you mean, my dear Ferdinand?
"Yes, mamma: I was reading that part of Harry and Lucy, in which their father so clearly explains to them the expansibility of air, and the power of steam; and I thought this might, perhaps, account for a thing that has always puzzled me extremely, and that is, earthquakes. [Footnote: Another remark of the child before mentioned.] I was reading a description of one a few days ago, and feel very anxious to know what can occasion such dreadful convulsions in the bowels of the earth. Will you be so kind, mamma, as to tell me what is supposed to be the cause?"
Mrs. B. On this, as well as on most other philosophical subjects, the opinions of the learned vary. Mr. *****, who was a great naturalist, imagines some to be produced by fire, in the manner of volcanoes; others, by the struggles of confined air, expanded by heat, and endeavouring to get free. But there does not appear any sufficient reason for this distinction. The union of fire and air seems necessary to effect the explosion; since the former is an agent of no power, without the aid of the latter.
Ferdinand. But pray, mamma, how does heat get into the inside of the earth?
Mrs. B. There are hidden in the bowels of the earth, immense quantities of inflammable matter: pyrites, bitumens, and other substances of a similar nature, which only require moisture to put their fires in motion. Water readily finds its way into the greatest depths of earth: or even from subterraneous springs, this dreadful mixture may occur, when immediately new appearances ensue; those substances which have lain dormant for ages, and which, had they not met with this new element, would have remained so for ages longer, appear suddenly to have changed their nature: they grow hot, produce new air, and require room for expansion. The struggles this air then makes to get free, throw all above into convulsions, and produce those dreadful catastrophes which we so properly denominate earthquakes. This appears the most rational means of accounting for this phenomenon; I have not, therefore, thought it needful to enter into the theoretical speculations of philosophers upon the subject.