Rocks, waves, and winds the shatter’d bark delay—
Thy heart is sad, thy home is far away.
But Hope can here her moonlight vigils keep,
And sing to charm the spirit of the deep.
Swift as yon streamer lights the starry pole,
Her visions warm the watchman’s pensive soul.
His native hills that rise in happier climes;
The grot that heard his song of other times;
His cottage home, his bark of slender sail,
His glassy lake, and broomwood-blossom’d vale,
Rush in his thought; he sweeps before the wind,
And treads the shore he sigh’d to leave behind!
Pleasures of Hope.
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[Illustration: Letter H.]
Hartlepool Lighthouse is a handsome structure of white freestone—the building itself being fifty feet in height; but, owing to the additional height of the cliff, the light is exhibited at an elevation of nearly eighty-five feet above high-water mark. On the eastern side of the building is placed a balcony, supporting a lantern, from which a small red light is exhibited, to indicate that state of the tide which will admit of the entrance of ships into the harbour; the corresponding signal in the daytime being a red ball hoisted to the top of the flag-staff. The lighthouse is furnished with an anemometer and tidal gauge; and its appointments are altogether of the most complete description. It is chiefly, however, with regard to the system adopted in the lighting arrangements that novelty presents itself.
The main object, in the instance of a light placed as a beacon to warn mariners of their proximity to a dangerous coast, is to obtain the greatest possible intensity and amount of penetrating power. A naked or simple light is therefore seldom, if ever employed; but whether it proceed from the combustion of oil or gas, it is equally necessary that it should be combined with some arrangement of optical apparatus, in order that the rays emitted may be collected, and projected in such a direction as to render them available to the object in view; and in all cases a highly-polished metal surface is employed as a reflector.
[Illustration: HARTLEPOOL LIGHTHOUSE.]
In the Hartlepool Lighthouse the illuminative medium is gas. The optical apparatus embraces three-fourths of the circumference of the circle which encloses the light, and the whole of the rays emanating from that part of the light opposed to the optical arrangement are reflected or refracted (as the case may be), so that they are projected from the lighthouse in such a direction as to be visible from the surface of the ocean.
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[Illustration: Letter C.]