In the Track of the Troops | Page 4

reality it does not. One of the best
detonators is fulminate of mercury. Detonating caps are therefore made
of this, and one such cap put into the middle of that cartridge of
dynamite and set fire to, by any means, would convert the cartridge
itself into a detonator, and explode it with a shattering effect.
"A human being," I continued, "sometimes illustrates this principle
figuratively--I mean the violent explosion of a large cartridge by means
of a small detonator. Take, for example, a schoolmaster, and suppose
him to be a dynamite cartridge. His heart is a detonating cap. The
schoolroom and boys form a galvanic battery. His brain may be likened
to a conducting-wire. He enters the schoolroom; the chemical elements
are seething in riot, books are being torn and thrown, ink spilt, etcetera.
Before opening the door, the good man is a quiet piece of plastic
dynamite, but the instant his eye is touched, the electric circuit is, as it
were, completed; the mysterious current flashes through the brain, and
fires his detonating heart. Instantly the gleaming flame shoots with
lightning-speed to temples and toes. The entire man becomes a
detonator, and he explodes in a violent hurricane of kicks, cuffs, and
invective! Now, without a detonator--a heart--the man might have
burned with moderate wrath, but he could not have exploded."
"Don't try illustration, Jeff," said my plain-spoken mother, gently
patting my arm; "it is not one of your strong points."
"Perhaps not; but do you understand me?"
"I think I do, in a hazy sort of way."
Dear mother! she always professes to comprehend things hazily, and
indeed I sometimes fear that her conceptions on the rather abstruse
matters which I bring before her are not always correct; but it is
delightful to watch the profound interest with which she listens, and the

patient efforts she makes to understand. I must in justice add that she
sometimes, though not often, displays gleams of clear intelligence, and
powers of close incisive reasoning, that quite surprise me.
"But now, to return to what we were speaking of--my future plans,"
said I; "it seems to me that it would be a good thing if I were to travel
for a year or so and see the world."
"You might do worse, my boy," said my mother.
"With a view to that," I continued, "I have resolved to purchase a yacht,
but before doing so I must complete the new torpedo that I have
invented for the navy; that is, I hope it may be introduced into our navy.
The working model in the outhouse is all but ready for exhibition.
When finished, I shall show it to the Lords of the Admiralty, and after
they have accepted it I will throw study overboard for a time and go on
a cruise."
"Ah, Jeff, Jeff," sighed my mother, with a shake of her head, "you'll
never leave off till you get blown up. But I suppose you must have your
way. You always had, dear boy."
"But never in opposition to your wishes, had I? Now be just, mother."
"Quite true, Jeff, quite true. How comes it, I wonder, that you are so
fond of fire, smoke, fumes, crash, clatter, and explosions?"
"Really," said I, somewhat amused by the question, "I cannot tell,
unless it be owing to something in that law of compensation which
appears to permeate the universe. You have such an abhorrence of fire,
fumes, smoke, crash, clatter, and explosions, that your only son is
bound, as it were, to take special delight in chemical analysis and
combination, to say nothing of mechanical force and contrivance, in
order that a balance of some sort may be adjusted which would
otherwise be thrown out of order by your--pardon me--comparative
ignorance of, and indifference to such matters."
"Nay, Jeff," replied my mother, gently, with a look of reproof on her

kind face; "ignorance if you will, but not indifference. I cannot be
indifferent to anything that interests you."
"True; forgive me; I should have said `dislike.'"
"Yes, that would have been correct, Jeff, for I cannot pretend to like the
bursting, smoking, and ill-smelling things you are so fond of; but you
know I am interested in them. You cannot have forgotten how, when
you were a boy, I used to run at your call to witness your pyrotechnic,
hydraulic, mechanic, and chemic displays--you see how well I
remember the names--and how the--"
"The acids," I interrupted, taking up the theme, "ruined your carpets
and table-cloths, and the smoke stifled and blinded, while the noise and
flames terrified you; no, mother, I have not forgotten it, nor the patient
way you took the loss of your old silk dress, or--"
"Ah! yes," sighed the dear old lady, with quite a pitiful look, "if