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veyors of the navy were chosen, " had no opportunity of acquiring even the common education given to men in their rank of life, and that they rise to the complete direction of the construction of ships, on which the safety of the empire depends, without any care or provision being taken on the part of the public that they should have any instruction in mathematics, mechanics, or in the science or theory of shipbuilding." The death blow to this lamentably imperfect system was, however, given by the establishment of the college.

Our author has given a forcible outline of the course of studies pursued at this admirable institution. After a severe contest before admission, the successful candidates remain seven years at the college, pursuing geometry, algebra, trigonometry, in all their important applications, examining the theoretical and practical details of mechanics and hydrostatics, and closing their purely mathematical inquiries by an enlarged course on the differential and integral calculus. After obtaining sufficient elementary knowledge, they are employed in constructing original designs of ships of war, ascertaining their displacements, and of the whole masses of the ships and their equipments, considered as heterogenous bodies. To this is added the most exact and accurate inquiries connected with the stability, both according to the metacentric method of Bouguer, and to the more perfect and precise investigation of Atwood. Comparisons are also instituted, the quality of English ships are compared with those of a foreign build, their several properties are analyzed, the good qualities are combined so as to remedy the bad, and to produce in their ultitimate application the most perfect design.

But it is not to theory only, that their attention is directed. The practical details of the art receive a large portion of their attention. They are effectually taught how to lay off ships in their practical construction, and in making drawings which are necessary for the execution of the work, in the progress of the building. The adze and

the line are put into their hands, like the humble operative at the dock-side, and a vigilant practical ship-wright examines into the minutest details of their duty. Engaged, therefore, in the morning, we will suppose, in studying the theory of their profession, in calculating the displacement, in investigating the properties, of the midship section, or endeavouring to catch a glimpse of the deep and recondite laws that regulate the resistance of fluids, they turn in the afternoon to the practical details of their art, in shaping or adjusting timbers, fitting up the component parts of the seppings' diagonal framing, bolting together the timbers of his circular sterns, and observing in those numerous cases, which the eye of theoretic intelligence is in general so ready to catch, the actual application of rules which occupied their morning thoughts. What else, our author asks, is necessary to make a complete and perfect ship-wright? The members of the college have the amplest and best theories continually before them, and the most enlarged practice to exemplify their application.

Our author, however, closes this part of his paper with an admonition, which will not, we hope, be neglected in the proper quarter. The studies of the members of the college, says he, are but begun, when the term which marks their residence has expired. Naval aachitecture is a jealous mistress, and requires the undivided man. Not the devotion of a few years, but of a life consecrated to its pursuits with unwearied zeal, must be devoted to its interests; and the cordial and uninterrupted pursuit of its varied details, must meet with the reward which attends the industrious labourer in other departments of the art.

We are glad to find, however, that our author, notwithstanding his able and vigorous defence of the college, has not neglected to consider the condition of the working men. Among the many operatives which a dock-yard presents, says he, there must be some few, at least, deserving of a better fate, than to spend the long term of their lives in a perpetual state of unceasing labour; some, though

working at first as humble shipwrights, yet deserving from their talents to rise to command. The great object, says the author, in a well regulated community, is to encourage ability, wherever it appears; and we are persuaded that the welfare of the country will be essentially promoted by fostering native talent."

"The section on the dimensions and forms of ships, is one replete with the most interesting inquiries. The gradual augmentation that our ships of war have received in their dimensions, is connected with the most interesting and important principles. A first-rate, constructed a century ago, is a vessel of quite a different class from a first-rate ofthe present day. Of such magnificent ships as the Britannia, the Prince Regent, or the St. George, our forefathers could have no conception. They are not only magnificent as exhibiting the mightiest combination of timbers ever constructed by man, but in future wars will develope energies more terrific than any exhibited at St. Vincent or Trafalgar. The Regent, of 1000 tons, constructed in the reign of Henry the Seventh, can bear no possible comparison to the Regent, of 2600 tons, constructed in the reign of George the Fourth! Spain was the first nation that increased considerably the dimensions of her different classes. of ships, and France followed her example with better success. In later times, the Americans have made some great steps in this important inquiry; and we rejoice to find that our own excellent naval administration have not lost sight of the subject. There are many advantages resulting from the enlargement of the dimensions of ships. It enables them to possess great stability, and thereby to carry a great press of sail with a comparatively small body immersed in the water; thus giving them a great moving power, in proportion to the resistance they experience, and thereby increasing their rate of sailing. Large dimensions also, in proportion to the number of guns, gives fine quarters to the men in action. It enables a finer form to be given to ships below the water, so that they have a good

entrance forward, and a clean run aft to the rudder, and to have the form best calculated to present great lateral reristance to the water, which prevents the ship from making much lee-way.

The only objection to this increase of dimension, is the expense; and possibly there are some limits beyond which it cannot be carried. We are persuaded, however, that this limit has not yet been attained, and we earnestly press its consideration on our naval engineers."

XXVII--On Parabolical Cupped Patent Breeches, for Gun-Barrels. By the EDITOR.

It is now thirty years since the Editor, at the suggestion of a scientific mechanic, first applied the parabola to shape the cups of patent breeches for gun-barrels, instead of the spherical form generally given to them, and the effect of which spherical form, was to cause the shot propelled therefrom by the charge, to be continually reflected to and from the sides of the barrel, during its whole passage through it, to the great injury of its effect. Whereas, it is a known property of the parabola, to cause any body propelled from its surface, to proceed in direct parallel lines, without any crossing, as in the case of the spherical cups. This parabolical shape likewise affords great facility and convenience in cleaning the cups, after the day's shooting; whereas the spherical cups are very difficult to clean. The Editor recommended this parabolical form of the cups to his friend Mr. Samuel Nock, a respectable gun-maker in this metropolis, twelve years ago; who immediately saw the great advantages of it, and has constantly adopted it ever since. He, however, has lately complained to the Editor, that another London gun-maker is now advertizing the parabolical cupped breeches as a new discovery; and it is therefore but fair to state the above particulars of the original application thereof by the Editor, thirty years ago; and its adoption, twelve years since, by Mr. Nock.

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LIST OF PATENTS FOR NEW INVENTIONS,

Which have passed the Great Seal since January 12, 1830.

To William Hale, of Colchester, in the county of Essex, machinist; for a machine or method of raising or forcing water, for propelling vessels. Dated January 12, 1830.-To be specified in six months.

To James Carpenter, of Willenhall, in the parish of Wolverhampton, in the county of Stafford; and John Young, of Wolverhampton, aforesaid, locksmiths; for certain improvements in locks, and other securities, applicable to doors, and other purposes. Dated January 18, 1830.-In six months.

To William Parr, of Union-place, City-road, in the county of Middlesex; for a new method of producing a reciprocating action by means of rotary motion, to be applied to the working of all kinds of pumps, mangles, and all other machinery, in or to which reciprocating action is required or may be applied. Dated January 18, 1830.-In four months.

To Edward Dakeyne, aud James Dakeyne, both of Darley Dale, in the county of Derby, merchants; for a machine, or hydraulic engine, for applying the power or pressure of water, steam, and other elastic fluids, to the purpose of working machinery, and other uses requiring power, and which is also applicable to raising or forcing of fluids. Dated January 21, 1830.-In six months.

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