THE ORIGINAL PREFACE.

same reason also here are not given any views of bridges,but only prints of such parts or figures as are necessary inexplaining the elementary parts of the subject.

As uiy profession is not that of an architect, very probablyI should never have turned my thoughts to this subject, so asto address the public upon it, had it not been for the occasionof an accident in that part of the country in which 1 reside,viz. the fall of Newcastle and other bridges on the riverTyne, on the 17th of November, 1771, occasioned by a highflood, which rose about 9 feet higher at Newcastle than theusual spring tides do. This occasion having furnished mewith many opportunities of hearing and seeing very absurdnotions advanced on the subject in general, I thought thedemonstrations of the relations of the essential parts of abridge, would not be unacceptable to those architects andothers, who may be capable of perceiving their force andeffects.

Newcastle, 1772.

The original edition, of 1772, being out of print, and thebook being much asked for, a new edition was printed in1801, at a time when the project of a cast-iron bridge of onearch, proposed to be built over the Thames at London, byMessrs. Telford and Douglass, was the subject of much con-versation : on which occasion the following addition was madeto the Preface; viz.

This little work, which was hastily composed on a parti-cular occasion, having been long out of print, is now as sud-denly reprinted in the same form, on the present occasion, ofthe report of a new bridge proposed to be thrown across theThames, at London: reserving the long intended edition, ona much larger and more improved plan, till a more conve-nient opportunity.

Royal Military Academy, Jan. 12, 1801.

It may here be added, that the whole tract has been nowquite re-cast and composed, and greatly enlarged with more

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