reason that it is both sightly and inexpensive. When taken to task for using it, as often happens, he replies, "Good concrete protected with steel is better than poor masonry."

In respect to the thickness of steel to use, the author's practice is to adopt half an inch below the ordinary stage of water and three eighths of an inch above, although for cheap bridges he occasionally shades these thicknesses one sixteenth of an inch.

For the coping of such piers stone may be employed; but it is preferable to put on a moulding of sheet metal, as this is more in keeping with the rest of the pier. This style of coping has been criticised on the plea that it is false, and that it has no direct function; nevertheless, the author considers it eminently proper to use it, and that its function is simply to beautify the construction by relieving the harsh outlines. Where stone coping is not used, the top of any kind of concrete pier may be finished off with either rich concrete of small broken stone or with granitoid, mixed in the proportion of one part of Portland cement, two parts fine granite screenings, and three parts of small crushed granite.

Cylinder piers filled with concrete are the most common kind of pier in America, and they are certainly the worst; nevertheless they have their place in good construction, when they are properly designed and built. Their abuse is due mainly to the builders of cheap highway bridges, who think that if the top of the cylinder is simply large enough to hold the pedestals, that is all which is necessary, no matter how high the piers may be, how great may be the scour, or what kind of foundation there is. If piles are employed as a foundation, they put in all that their small cylinders will hold, and never dream of its being necessary to figure how many tons each pile will have to sustain.

Cylinder piers are legitimate construction in places where, under the worst possible conditions in respect to scour, they will have a firm grip in solid material, say not less in depth than twenty per cent of the height of the entire pier.

Cylinder piers will not often stand the test of the curve of pressures herein  described for masonry piers;  but this is not