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xvi In connection with these algebraical articles, the treatise on Annuities and Assurances on Lives, by Mr Joshua Milne, may be mentioned; in which, however, its experienced author, by a useful division of his subject, has addressed himself as well to those who have not, as to those who have, an acquaintance with Algebra.

The articles in Natural Philosophy are numerous and various; extending through every head of that great division of Physical Science.

To the head of Mechanics, may be referred the valuable article Bridge, by Dr Young, and that on Weights and Measures by the same author; both containing the substance of all the more recent discussions in regard to the principles involved in their respective subjects. The article Pendulum, written by M. Biot, belongs also to this head. Besides explaining the laws of the motion of this instrument, it describes, at considerable length, the principal purposes to which it has of late been applied in the physical sciences.

Capillary Attraction, and the Cohesion of Fluids, subjects shortly explained in the general treatise under the head of Hydrodynamics, in the Encyclopædia, have been resumed in this work, for the purpose of fuller discussion, and the statement of some later views and experiments. The article on the first of these subjects was contributed by Mr Ivory; that on the other by Dr Young; who has also, in an article on Hydraulics, written as a supplement to the general treatise just mentioned, explained the later attempts to improve the theory of this branch of science. The articles on Breakwaters, and on Docks, may be mentioned as contributions to the division of Natural Philosophy now in view; because relating to works whose construction depends on hydrostatic and hydraulic principles. ‘The first is particularly valuable, as containing an accurate account of the two greatest works of the kind in existence—the one at Cherbourg, the other in Plymouth Sound; the latter, now nearly completed, constituting one of the many durable monuments of the great professional genius and resources of the late eminent Engineer, Mr Rennie. For this article, and many others, the Editor is indebted to the distinguished assistance of Mr Barrow; who has enriched the work with much valuable and various information, that could not have been obtained in so satisfactory a form, if at all, from any other quarter.