127. The value of concrete, as a substitute for stone and brick, has been known for many centuries, and is to be seen in the ruins of ancient Roman temples and palaces, in domes and arches, in the core or interior of brick-faced walls, and in their foundations.

Although, for many years past, engineering works of great extent have been constructed of concrete, it is only within a quite recent period that this valuable material has come into considerable use in this country for building purposes, except as footings for foundation walls, for which it has long been used. Although it is not probable that concrete will ever entirely take the place of stone and brick, yet, both alone and in combination with iron and steel, it is of great value for various constructive purposes. Suitable materials for the manufacture of concrete can be found in almost every locality, which, with its comparative cheapness, makes it an important substitute for brick and stone in ordinary structures. In many places, cottages, and even large edifices, have been built of concrete. Instances of the magnitude of such construction are several very large hotels at St. Augustine, Fla. In one of these, the basement is a bathing pool 100 feet long, 60 feet wide, and from 3 to 10 feet deep, constructed entirely of concrete. This basin is surrounded by columns 6 feet square at the bottom, and 40 feet high, carrying concrete arched beams of 25 feet span, supporting the roof over the interior court.