Imagens das páginas

(Lanfrancus) proverit. The correctness of this representation is proved by appearances in that most ancient and magnificent fabric both within and without. The nave has plainly been extended westward; but if the eastern part of it be not a remnant of the individual church of the Saxon convent, as constructed in the reign of Edgar out of the bricks of Verolamium, the union of square pieces and round massy arches, affords no decisive symptom, even when confirmed by external evidence, of the genuine ante-Norman architecture. Secondly, the old choir at Canterbury (that of Lanfranc) was covered with a fat ceiling ornamentally painted, to which the corresponding note adds, This is the actual state of the grand abbatial church of St. Alban's, and of other ancient churches.'. To us it appears beyond a donbt, that the ceiling of this church is a flat roof of the fifteenth century, with fluted intersecting ribs; and that the inscription painted upon the pannels, is the common black letter of the same era. Thirdly, the period at which Dr. Milner fixes the introduction of a truly Gothic and barbarous style, ought to have been rather more indefinite. The ruin,' he says,

was complete when Edward the Sixth mounted the throne in the sixteenth century. “Then began a style, consisting of irregular and ill-executed Grecian members, with intermixed globes, triangles, frets, pyramids, obelisks, &c. as may be seen on all the ornamental tombs and other works executed in England, between the close of the reign of the last Henry and the early part of the reign of the first Charles, by whose taste and munificence, aided by the genius of Inigo Jones, true Grecian architecture was introduced into this island.' p. 117. The compliment to the unfortunate Charles, the elegant and judicious patron of all the fine arts, is highly proper; but the foregoing propositions are exceptionable, inasmuch as some tombs, of a debased Grecian composition, are found in the earlier part of Henry the Eighth ; while others purely and strictly English, are met with in the reign of Mary. Of the former, the monument of Dean Colet, who died in 1519, is an example: of the latter, the tomb of King, the first Bishop of Oxford, at Christ Church, 1556, and that of Chaucer, if indeed it were more than repaired by Brigham, in 1555.

We have been detained on this enchanted ground till the review approaches in quantity of matter to the work reviewed. We now take leave of Dr. Milner, earnestly wishing that, while the cathedrals of Litchfield and Salisbury operate as a warning, his little volume may become a practical manual to every chapter in the kingdom. For the pleasure, the refreshment of spirits, (a sensation produced as much by the work as the subject, with which we have perused it, he has our warmest thanks. Seasons of gratification, in a career like ours, occur seldom; and never continue long. They are like the few luminous and cheerful days of a dark and gloomy life. • Exigro gratoque fruaris tempore raptim. It is the calamity of the present era of literature, that the soundest information, the most valuable discoveries, are too frequently conveyed in a jargon abusively denominated English. While science is multiplied, we are losing our mother tongue. Wearied and disgusted with toiling through more than one ponderous volume, as good and as bad as those which we have described, we came prepared to enjoy, with all the zest arising from contrast, the rich and classical treat of a controversy between two such men as Dr. Milner and Mr. Whittington, conducted in the temper of gentlemen, and in a style of purity and precision attainable only by scholars. When subjects so elegant and entertaining descend into the hands of mere draftsmen, and engravers, we could readily pardon a style at once slovenly and ungrammatical, for the sake of the valuable information which they are often able to convey; but these tradesmanlike faults are not, now a-days, those which demand forgiveness : on the contrary, praise is challenged for affectation which sickens, for tumour which provokes at once to anger and to laughter. Against such writers and such writings, as we love the good old style of our forefathers, we are compelled to make a stand. It is with language as with architecture; gorgevusness precedes affectation, and affectation is the parent of barbarism. In the hands of such artists, the English tongue is even now become an irregular and ill executed medley of Grecian and Roman members, • with intermixt and incongruous frets, triangles, pyramids, obelisks, and other absurd devices ;' and it is for the authority of Dr. Milner, and such judges as Dr. Milner, to deliver us either from the one or the other.

tion, such

Art. IV. New Theory of the Tides. By Ross Cuthbert, Esq.

Quebec printed; London reprinted. 8vo. pp. 20. W!

E are not induced to turn our attention to the subject of the

tides, either by the intrinsic importance of this essay, or by the scientific reputation of the quarter of the globe in which it originated. But it happens to state, with tolerable precision, some objections to the received opinions respecting the tides, which have been advanced by former writers, and which are at present entertained by many persons, who appear in other respects to be well informed. We therefore willingly take the opportunity of endeavouring to answer these objections, and to lay before our readers such an explanation of the true theory, as, we hope, will render it intelligible to some of those who have bitherto been at a loss to comprehend it. After having said that Mr. Cuthbert attempts to deduce from a supposed expansion of the sea, occasioned by the daily variations of the solar heat, the plenomena of the tides, which, wherever they have been observed, have most indisputably maintained, for whole centuries, a lunar period, following, without the slightest deviation, the mean motion of the moon, it will scarcely be necessary to add another syllable, either in illustration or in confutation of so extravagant an opinion; and we shall contine ourselves in great measure to the task of refuting the objections to the Newtonian theory, which are thus stated in our author's preface.

Whatever in science has been sanctioned by Sir Isaac Newton should perhaps be privileged from inspection, and taken for truc. But it often happens that human genius, weary as well as proud of success, will seek repose in arbitrary explanations of the phenomena it has found difficult to solve. The cause of the tides, seems in this way to have been ascribed chiefly to the moon's attraction; evidently in consequence of an occasional, but very irregular, correspondence between its changes and the variations of the tides. However, the moon and the tides have not the pretended coincidence of change; the experience of every month proves their disagreement; that high water sometimes takes place, even three hours after the time when the moon's supposed disturbing force is greatest; and low water within three hours of the same period, and even at the same time. The supposition that the gravity and viscidity of water prevents its promptly obeying the moon's force, would be well founded if the moon's changes were sudden. But the moon's progress is slow; and, consequently, had the moon the disturbing force attributed to her, the changes in the waters which partly cover the globe would necessarily be regular: high water would take place precisely when the moon's force was greatest, and would steadily follow the moon in her progress.

Theory admits and requires, that the attraclion of the moon, detached and distant as it is from the earth, is sufficient to controul, and therefore greater than, the various opposing forces, of ist, gravity, whereby the particles of water are drawn and bound to the common centre of the globe, of which they form a part; adly, the attraction of cohesion, acting mutually on the particles in contact with each other. • It is further assu

sumed, that the waters of the globe are raised in the region immediately beneath the moon, and at the antipodes of that region, at the same time; so that the moon attracts one side of the globe, and repels the other.

• The sun and moon, in conjunction or opposition, are required to produce the same effect. Thus the sun and moon, acting together on ihe same radius, on the principle of attraction are supposed to disturb the waters of our globe, in the same way as when the sun is acting in exact opposition to the moon.

« The

· The moon's attraction must be a tendency to approach the whole mass of our globe : but not to derange or disunite its parts.

Could the moon's attraction disturb the waters of our globe, one wave or tide only, would perpetually follow the moon; and, instead of two high and two low tides, at each place, in twenty four hours, there would be but one tide during that time.'

Of these objections the most material seems to be, that, according to the Newtonian opinion, the moon must be supposed to repel the waters on the remoter side of the earth, instead of attracting them. The next is, that the lunar attraction must be sufficient to overcome the forces of gravity and cohesion. The third, that the time of high water is frequently three, and sometimes six hours later than that of the moon's passage over the meridian.

The difficulty in conceiving the apparent repulsion of the waters on the romoter side of the earth, which very naturally occurs to one who is but little conversant with the subject, appears to depend on a want of sufficient attention to the manner in which the mean solar and lunar attractions are counterbalanced. We are unconsciously disposed to consider the earth, especially in comparison with the moon, as a body perfectly at rest, or at most as an immense sphere poised on its axis, or having some secret support connected with its centre. And it is true that if the earth were suspended as an apple hangs on its stalk, or a terrestrial globe on the pins which connect it with the brazen meridian, the attractive force of a distant body would necessarily tend to collect a fuid surrounding it, about the part nearest to the disturbing body. But the force counteracting the solar and lunar attraction is by no means to be confounded with the operation of a support of any kind, attached to the solid parts of the sphere alone ; for the force actually concerned in this case is equally efficacious with respect to the fluid parts, and, acting exactly alike on each particle of the earth and sea, it precisely counterbalances the mean force of attraction, and leaves only the difference of the attractive powers, which are different for the different parts of the earth and sea, to exhibit its effects in disturbing the relative situations of those parts. This counterbalancing power is well known under the name of the centrifugal force, being derived from the velocity of the earth either in its annual revolution round the sun, or, in the case of the moon, from its velocity in revolving round the common centre of inertia of the earth and moon. Since the earth actually falls at every instant as much within the tangent of its annual orbit, or the temporary line of direction of its motion, as it would descend towards the sun in an equal time, if it were otherwise at rest, this change of relation of the revolving body, which prevents its actual approach to the centre of attraction, and counteracts the force of gravitation, is, not impro

perly, perly, considered as constituting a distinct force, and is characterized by the term centrifugal. Before the introduction of the Newtonian theory, an attempt was made, by the celebrated Dr. Wallis, to deduce the tides from a difference of the centrifugal forces affecting the opposite parts of the earth and sea, in revolving round the sun and round the common centre of gravity of the earth and moon, and Mr. Ferguson, in later times, has endeavoured to explain an opinion of a similar nature, by means of the whirling table; but the apparatus of Ferguson was so constructed as to produce a greater velocity of rotation in the remoter than in the nearer parts of the revolving system of bodies, which is a difference that does not exist in the case to be investigated; for the velocity of the different parts of the earth and sea, with respect to their common annual revolution round the sun, is precisely the same, the diurnal rotation being altogether independent of this revolution, and producing modifications of force, which have their separate compensations, as distinctly indeed as the monthly revolution of the moon, which does not affect the velocity of its mean annual revolution round the sun, together with the earth. It is therefore so far from being true, that the inequality of the centrifugal force at different parts gives rise to any part of the phenomena of the tides, that, on the contrary, the perfect uniformity of this force is the basis of the determination of the powers immediately concerned in these phenomena. The Atlantic and the Pacific oceans are subjected to a centrifugal force precisely equal to that which affects the solid parts of the earth, but when the luminary is over the Atlantic, its attraction for that ocean is greater than for the central part, and consequently greater than the centrifugal force, so that this differential attraction tends to elevate the Atlantic; at the same time that its attraction for the Pacific ocean is less than the mean attraction, and less than the centrifugal force, which therefore prevails over the attraction, and the differential force tends to raise the Pacific ocean, almost as inuch as it tends to raise the Atlantic in the opposite direction. There is also an additional force, derived from the obliquity of the action of the luminary on the parts of the earth not immediately below it, which tends to compress the lateral parts, and to increase the elevation. The readiest way of calculating the operation of all these forces is, to reduce them to a horizontal direction, and to determine what inclination of each part of the surface of the sea, considered as an inclined plane, will cause such a tendency, in a particle situated on it, to move in a contrary direction, as precisely to counterbalance, not only these forces, but also the new disturbing force, derived from the attraction of the parts thus elevated; and it may easily be shown, that all these conditions will be fulfilled, if we attribute to the surface of the sea the


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