Much however depends on the firſt communication of any ſcience to a learner, though the beſt and most eaſy methods are ſeldom adopted. Propoſitions are placed before a ſtudent, who though having a ſufficient underſtanding, is told just as much about them on entering at the very threſhold of the ſcience, as gives him a prepoſſeſſion moſt unfavourable to his future ſtudy of this delightful ſubjeƈt; or "the formalities and paraphernalia of rigour are so oſtentatiously put forward, as almoſt to hide the reality. Endleſs and perplexing repetitions, which do not confer greater exactitude on the reaſoning, render the demonſtrations involved and obſcure, and conceal from the view of the ſtudent the conſecution of evidence." Thus an averſion is created in the mind of the pupil, and a ſubjeƈt so calculated to improve the rationing powers, and give the habit of cloſe thinking, is degraded by a dry and rigid courſe of inſtruƈtion into an unintereſting exerciſe of the memory. To raiſe the curioſity, and to awaken the liſtleſs and dormant powers of younger minds ſhould be the aim of every teacher; but where examples of excellence are wanting, the attempts to attain it are but few, while eminence excites attention and produces imitation. The objeƈt of this Work is to introduce a method of teaching geometry, which has been much approved of by many ſcientific men in this country, as well as in France and America. The plan here adopted forcibly appeals to the eye, the moſt ſenſitive and the moſt comprehenſive of our external organs, and its pre-eminence to imprint it ſubjeƈt on the mind is ſupported by the incontrovertible maxim expreſſed in the well known words of Horace:
Segnius irritant animos demiſſa per aurem
𝓠uàm quæ ſunt oculis ſubjeƈta fidelibus.
A feebler impreſs through the ear is made,
Than what is by the faithful eye conveyed.
