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tions of figure and quantity, it likewise accustoms the mind to the invaluable exercise of patient attention and accurate reasoning. Of these distinct objects, the last is perhaps the most important in a course of liberal education. For this

purpose,

the geometry of the Greeks is the most powerfully recommended, as bearing the stamp of that acute people, and displaying the finest specimens of logical deduction. Some of the propositions, indeed, might be reached by a sort of calculation; but such an artificial mode of procedure gives only an apparent facility, and leaves no clear or permanent impression on the mind.

We should form a wrong estimate, however, did we consider the Elements of Euclid, with all its merits; as a finished production. That admirable work was composed at the period when

geometry was making it's tíost rapid advances, and new prospects were opening on every side. No wonder that its structure should now seem loose and defective. In adapting it to the actual state of the science, I have therefore endeavoured carefully

to retain the spirit of the original, but have sought to enlarge the basis, and to dispose the accumulated materials into a regular and more compact system. By simplifying the order of arrangement, I hope to have considerably smoothed the toil of the student. The numerous additions which are incorporated in the text, so far from retarding, will rather facilitate his progress, by rendering more continuous the chain of demonstration. To multiply the steps of ascent, is in general the most expedie tious mode of gaining a summit.

The view which I have given of the nature of Proportion, in the fifth Book, will, I flatter myself, be found to remove the chief difficulties attending that important subject. The sixth Book, which exhibits the application of the doctrine of ratios, contains a copious selection of propositions, not only beautiful in themselves, but that pave

the

way to the higher branches of Geometry, or lead immediately to"valuable practical results. Yet the Appendix, without claiming the same degree of utility, will not be deemed the least interesting

portion of the volume, since the ingenious resources which it discovers are calculated to afford a very pleasing and instructive exercise.

The part which has cost me the greatest pains, is that devoted to Geometrical Analysis. The first Book consists of a series of the choicest problems, rising above each other in gradual succession. The second and third Books are almost wholly occupied with the researches of the Ancient Analysis. In framing them, I have consulted a great variety of authors, some of whom are of difficult access. The labour of condensing the scattered materials, will be duly estimated by those, who, taking delight in such fine speculations, are thus admitted at once to a rich and varied repast. The analytical investigations of the Greek geometers are indeed models of simplicity, clearness, and unrivalled elegance; and though miserably defaced by the riot of time and barbarism, they will yet be regarded by every person capable of appreciating their beauties, as some of the noblest monuments of human genius. It is matter of deep regret, that Algebra,

or the Modern Analysis, from the mechanical facility of its operations, has contributed, especially on the Continent, to vitiate the taste and destroy the proper relish for the strictness and purity so conspicuous in the ancient method of demonstration. The study of geometrical analysis appears admirably fitted to improve the intellect, by training it to habits of precision, arrangement, and close application. If the taste thus acquired be not allowed to obtain undue ascendancy, it may be transferred with eminont utility to Algebra, which, having shot up prematurely, wants reform in almost every department.

The Elements of Trigonometry are as ample as my plan would allow. I have explained fully the properties of the lines about the circle, and the calculation of the trigonometrical tables; nor have I omitted any proposition which has a distinct reference to practice. The last problem is of essential consequence in marine surveying.

Having already exceeded the ordinary limits, it perhaps unfortunately became requisite to curtail

the Notes and Illustrations, with which the volume concludes : Yet the more advanced student may peruse the few historical and critical remarks with considerable advantage. Some of the disquisitions, and the solutions of certain more difficult problems relative to trigonometry and geodesiacal operations, in which the modern analysis is sparingly introduced, are of a nature sufficiently interesting, I would presume, to claim the notice of proficients in sci.

ence.

The printing of this Treatise has, owing to a combination of retarding circumstances, been attended with infinite trouble, vexation, and delay. The time consumed in urging the press would have been more agreeably employed in prosecuting phy. sical inquiries, and fulfilling the engagements already contracted with the public. But, in making such a sacrifice, I should consider myself abundantly rewarded, if I could indulge the hope that my exertions may, in some degree, contribute to revive among us the passion for genuine science, which, at least in this northern part of the island, has been chilled by neglect, or suffered to languish

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