Page:Travels to Discover the Source of the Nile - In the Years 1768, 1769, 1770, 1771, 1772, and 1773 volume 1.djvu/25

Rh de la Nature of the Abbé Vertot. But the present one was constructed upon my own principles; I intrusted the execution of the glasses to Messrs Nairne and Blunt, Mathematical instrument-makers opposite to the Exchange, whom I had usually employed upon such occasions, and with whose capacity and fidelity I had, after frequent trials, the greatest reason to be satisfied.

, when finished, became a large and expensive instrument; but being separated into two pieces, the top and bottom, and folding compactly with hinges, was neither heavy, cumbersome, nor inconvenient, and the charge incurred by the additions and alterations was considerably more than compensated by the advantages which accrued from them. Its body was an hexagon of six-feet diameter, with a conical top; in this, as in a summer-house, the draughtsman sat unseen, and performed his drawing. There is now, I see, one carried as a show about the streets, of nearly the same dimensions, called a Delineator, made on the same principles, and seems to be an exact imitation of mine.

means of this instrument, a person of but a moderate skill in drawing, but habituated to the effect of it, could do more work, and in a better taste, whilst executing views of ruined architecture, in one hour, than the readiest draughtsman, so unassisted, could do in seven; for, with proper care, patience, and attention, not only the elevation, and every part of it, is taken with the utmost truth and justest proportion, but the light and shade, the actual breaches as they stand, vignettes, or little ornamental shrubs, which generally hang from and adorn the projections and edges of the several members, are finely expressed, and beautiful lessons given, Vol I.