el
gripe, and, opening it, threw down a little shower of scintillating
dust, an airy fall of powdered diamonds, lost as they readied the earth,
and that was all.
"We're casting some of those Fresnel lanterns to-day. Perhaps the ladies
would like to see them," suggested the pale little old man, and pointed
to a powerful machine with a long lever-handle at the top, which, being
thrown up, showed a heavy iron mould, heated quite hot, and just now
smoking furiously from a fresh application of kerosene-oil, with which
the mould is coated before each period of service, much as the housewife
butters her griddle before each plateful of buckwheat cakes.
As the smoke subsided, the old man, who proved a very intelligent as
well as civil person, thrust his pontil into the pot nearest the press,
and, withdrawing a sufficient quantity of the glass, dropped it squarely
into the open mould, whose operator, immediately seizing the long
handle, swung himself from it in a grotesque effort to increase the
natural gravity of his body, and succeeded in bringing it down with
great force. Then, leaning over the lever in a state of complacent
exhaustion, he glared for a moment at the spectators with the calm
superiority of one who, having climbed to the summit of knowledge, can
afford to pity the ignorant crowd groping below.
The mould being reopened presently displayed a large, heavy lantern,
whose curiously elaborate flutings and pencillings were, as the
intelligent artisan averred, arranged upon the principle of the famous
Fresnel light, whose introduction some years ago marked an epoch in the
history of light-houses.
"Why, Miss, these little up-and-down marks, that you'd take it were just
put in for fancy," said William Greaves, "have got a patent on 'em, and
no one else could put 'em into a lantern without being prosecuted."
"But why? What difference do they make?"
"Why, Miss, every one of them fingerings makes a lens; you see it's just
the same inside as out, and it sort of _spreads_ the light. That a'n't
the way to call it, but that's the idea; for the man that got it up was
down here, and I talked with him."
"And what are they for?"
"For ships' lanterns, Ma'am. They take this round lantern, when it's all
done here, and split it in two halves up and down, and then put one on
each side a vessel's bows just like the lamps on a doctor's gig, and the
bowsprit runs out between just like the horse does in the gig."
At this
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