PREFACE. IT has been remarked, that when a business is conducted by precedent alone, it must remain without improvement; and that the best method of improving a business is to study it as a science. Now, there are two modes by which knowledge may be acquired the one by reasoning from first principles; the other by reasoning from experiments and observations of facts. But the best course is to unite the two methods, when the talent of the inquirer is equal to the task. If it were only as examples of the method of reasoning from experiments and facts, the papers of SMEATON in their complete state are truly valuable; but it also fortunately happens that they are on subjects which form part of the business of the engineer and millwright, and which ought to be well understood by the Civil Engineer. The experiments of VENTURI are of a similar nature, and illustrate some curious phenomena of considerable importance; and those intrusted with the management of rivers, drainage, and the supply of water by pipes, may study his experiments with much advantage. In judgment he seems as much inferior to Smeaton, as he is superior to him in mathematical learning. Hence it will be found that he sometimes builds too much on the data of his experiments. Of the value of Dr. YOUNG'S Summary of Hydraulics we have already given our opinion in the advertisement which precedes it; and we have only to add that the motion of water in rivers, the inclination of their surfaces, and the velocity of water in pipes, are there given in a more brief and clear manner than in any other work extant, and may be usefully referred to in questions relative to right of water in arbitrations, &c., as well as in calculations for new water-works. To these, BossUr's Experiments on Water Wheels, and Notes, either to illustrate theoretical principles or supply practical rules, where wanting, are added ; the whole forming a collection which will be a useful course of study for a young man, and not without its value in the library of the regular professor. CONTENTS. I. SMEATON'S EXPERIMENTAL INQUIRIES. PAGE II.-An Experimental Examination of the Quantity and Pro- b |