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ART. II.-Some Account of an improved Mode of suspending Gazometers. By Robert Hare, Junr. Honorary Doctor in Medicine, and Member of various scientific Societies.

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IT T is well known to all who are conversant in gas light apparatus, that no mode has been heretofore devised to render gazometers accurately equiponderant at all points of their immersion in the water; a circumstance so indispensable to their action. The mode adopted in the large London Establishments, and which appears to be the most approved, is that of the gazometer chain. This is costly; difficult to execute well, and not susceptible of correction, when erroneously proportioned to the desired effect; especially after the apparatus is in operation. From all these faults, the method of suspension on a beam, like that in our cut, is entirely free. In practice it has answered perfectly: and, when we have described the mode of constructing such a beam, we think the rationale of its operation will become self-evident.

Find (by trial, if possible; if not, by calculation) the weight of the gazometer when sunk so low, as that the top will be as near as possible to the water, without touching it. In the same way find the weight of the gazometer at the highest

point of immersion, to which it is to rise, when in use. Then, as the weight in the last case, is to the weight in the first; so let the length of the arm A, be to the length of the arm B. From the centre D, with the radius A, describe a circle; on which set off an arch C, equal to the whole height through which the gazometer is to move. Divide this into as many parts as there are spaces in it, equal each to one-sixth of the radius or length of arm A. Through the points thus found, draw as many diameters; which will, of course, form a corresponding number of radii and divisions, on the opposite side of the circle. Divide the difference between the length of A and B, by the sum of these divisions: and let the quotient be q. From the center D towards the side E, on radius 2, set off a distance equal to the length of the arm A, less the quotient or q. On radius 3, set off a distance equal to A, less 2q, or twice the quotient; and so set off distances on each of the radii; the last being always less than the preceding, by the value of q. A curve line bounding the distances thus found, will be that of the arch head E. The beam being supported on a gudgeon at D, let the gazometer be appended at G; and let a weight be appended at F, adequate to balance it at any one point of immersion. This same weight will balance it at all other points of its immersion-provided the quantity of water displaced by equal sections of the gazometer be equal. But as the weights on which A and B were predicated, may not be quite correct; and as, in the construction of large vessels, equability of thickness and shape cannot be sufficiently attained-the consequent irregular buoyancy is compensated by causing the weight to hang nearer to, or farther from the centre, at any of the points taken in making the curve. This object is accomplished by varying the sliders seen opposite to the figures 1, 2, 3, 4, 5, 6. When they are properly adjusted, they are made firm by the screws of which the heads are visible in the diagram.

The drawing is of a beam twelve feet in length; and of course, the length of the arm A is six feet-that of B, four feet their difference two feet; which divided by 6, the number of points taken in making the curve E, gives four inches for the quotient q. Hence the distance on radius 2, was five feet eight inches on radius 3, five feet four incheson radius 4, five feet-on radius 5, four feet eight incheson radius 6, four feet four inches-and lastly four feet.

The iron gudgeon, where it enters the beam is square. The projecting parts are turned true, and should be bedded in brass or steel dies; placed, of course, on a competent frame.

The sixth part of a revolution of the portions of the gudgeon thus supported, is the only source of friction to which this beam is subject during the whole period of the descent of the gazometer;-which, in large ones, does not ordinarily take place in less than six hours.

ART. III.-Pilgrimage to the Holy Land: a Poem in two Cantos. To which is added, The Tempest, a Fragment. By Lord Byron. Philadelphia: republished by M. Thomas. 1817. pp. 65.

NOTWITHSTANDING the positive assertion, contained

in the advertisement of the London Editor, that the copyright of this little work was assigned to him by the noble author himself,' for the consideration of five hundred guineas, some doubts of its genuineness still linger on our mind. The character of Lord Byron's poetry is so marked and peculiar, that its rudest features may, without much difficulty, be imitated, or rather mimicked, so as to deceive a careless or superficial reader. But those fine touches of wild and deep pathos, interspersed in all his compositions, among a thousand crudities, are not so easily copied-and perhaps not to be equalled, by any living manufacturer of rhyme. For the sake, therefore, of the reputation of this wayward child of poesy, we cherish a hope, that these productions, denominated Poems, will appear, by future investigation, to have been, not the rickety offspring of his Lordship's fascinating muse; but the chef d'œuvre of some tyro poetaster, trying his wing in an imitation before he has acquired audacity to attempt a flight.

It is undeniable, that great poets sometimes write bad verses; but it is generally, because their subject is ungracious to their feelings or ill suited to their taste. No such excuse, however, can be imagined for the flatness, the vapid dulness, that pervades the Pilgrimage. Lord Byron's forte, we conceive, indisputably to be in portraying, by a splendid figure, or by inimitably forcible description, that gloomy state of dejected sensibility in hearts of sublime enthusiasm and exquisite feeling,-that consciousness of inward desolation, which he somewhere characterizes as the leafless desert of the mind.' And it is by so powerfully touching the chord in our bosoms, which vibrates in such a state of feeling that he forces us, in the might and majesty of his eloquence, to love the Corsair in spite of all his crimes, and to forgive the licentiousness of Childe Harold.

Having often experienced the magic of his numbers, we were led, by the title of the Pilgrimage, to anticipate the loftiest excitement of fancy and feeling, from so noble a subject, touched by so masterly a hand. The idea of the Holy Land, associated, as it is, with the recollection of all the romantic fictions of chivalry, and the not less romantic realities of the crusades,-besides the sacred scenes of the New Testament,-never fails to excite, in minds of no uncommon fervour, a crowd of enthusiastic sentiments, which blend the zealous ardour of piety with the more tempered sadness of reason, in a comparison of that most interesting country in her present debasement, with her past happiness and importance. With a subject so fit to touch the poet's hallowed lips with fire, we hoped Lord Byron's fervid fancy would

have been

'Not touched but wrapt, not wakened, but inspired.'

We thought he had, at last, found a theme capable of calling forth the full powers of his genius; and we entered upon the perusal with expectations perhaps unreasonably raised. But, whether the fault were the poet's or our own,-in proportion to our expectations was our disappointment. Instead of a fine bold rhapsody, glowing with sentiment and sparkling with metaphor, we waded through a spiritless, tame, prosing story of a voyage along the coast of France and Portugal and Barbary: and when at last we had come near the promised land where, as poets say,

Carmel's mount in hazy splendour drest

Drives through the obscuring mist its lofty crest,' we found no change in the style or sentiment,-no loftier tone of poetry excited; but the noble pilgrim, after a most farmer like reflection on the great crops of corn, which might be produced from the fertile soil of Syria, in these words:―

What pity that so fair, so kind a soil
That teems prolific at the touch of toil,

In whose dark breast rich mines of beauty lie
And lusty harvests hall the genial sky;

Where no foul blights the tender blossom wound
Nor cast the bud to wither on the ground,
What pity that a land so fairly graced

Like a rich wilderness should run to waste, &c.'

flies off to Spain, France and England; joins the opposition in parliament to demand a retrenchment of sinecures; and so arrives at his most lame and impotent conclusion.

We do not mean to say, however, that the poem is destitute of beauties. On the contrary, it has an unvaried pretti

ness throughout the whole, which would be as creditable to many writers as it is unworthy of Lord Byron. When we consider the work independent of all comparison with the former productions of its reputed author, we find many pleasing lines: For instance, the first stanza:

'Where the gay spirit of the morning sleeps

On orient vales and Galilean steeps-
Where hoary Lebanon its front uprears,
Ploughed with the furrows of six thousand years—
There is a land in olden records named

By seer and sage, by prophet, pilgrim famed,
Whose thirsty mountains piled in green array,
Drink from its golden source the stream of day,
Whose limpid kes in solitary pride

Through spicy meads their chrystal waters guide,
And Nature spreads her feast divinely fair,

As if some Deity still lingered there.'

And still better the following description of moon-light

at sea:

'Who that has traversed on the waters wide,
And marked the silver moon and starry pride
Lave their bright splendours in the ruffled tide:
Who that has seen with poet's frenzied eye,
The midnight glories of a cloudless sky;
Pouring their beacon blaze o'er beach and bay,
To guide that wanderer of the trackless way;
Who that has watched the frolic moon-beams ride
On the rough ridges of the billowy tide,

Like fairy-lights which come when seamen sleep
To sport in elfin gambols on the deep-

Who that has viewed the night's resplendent tire,
Till every feeling kindled into fire;

Would change the rapture of that holy hour,

For sordid joys or charms of pomp or power?

These specimens seem the most favourable we could select: yet how little can be discerned in them of the vivida vis animi of Lord Byron!

As to the Tempest, it is extremely mysterious; and, if the author intended that mystery should form its character and be its sole value, he has succeeded to his utmost wish: for the mystery is quite impenetrable; and other beauty (if that can be called beauty) it has none. It is a story of a shipwreck, and the funeral of a man thrown on shore; and the interest is attempted to be excited by not telling who or what the sufferer was; except that he had some secret grief, which he would not divulge. The poetry is common-place-and the greatest merit we could discover in the composition is its

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