The following is a chronologically arranged list of the author's various investigations and writings on the subject of bridge economics, extending over a period of thirty-seven years:

In 1883, a paper on "Economy in Struts and Ties."

In 1884, a chapter on "Economy" in "The Designing of Ordinary Iron Highway Bridges."

In 1891, a paper in "Indian Engineering" on "Economic Span-Lengths."

In 1897, a chapter on "True Economy in Design" in "De Pontibus."

In 1897, an elaborate investigation of the economics of cantilever bridges, published in the last-mentioned work.

In 1906, a complete investigation of the economics of steel trestles, which was later incorporated in "Bridge Engineering."

In 1907, an extensive paper on "Nickel Steel for Bridges," published by the American Society of Civil Engineers and awarded its Norman Medal.

In 1909, a paper written in French for Le Génie Civil and entitled "Une &Ecute;tude Économique de l'Emploi de l'Acier au Carbone á Grande Résistance pour la Construction des Ponts."

In 1913, a paper on "The Possibilities in Bridge Construction by the Use of High-Alloy Steels," published by the American Society of Civil Engineers, and awarded its Norman Medal.

In 1914, a paper on "Alloy Steels for Bridgework," presented to the International Engineering Congress of the San Francisco World's Fair.

In 1916, a chapter on "True Economy in Design," in "Bridge Engineering," being an expansion of a similar chapter in "De Pontibus."

In 1917, a series of three lectures on "Engineering Economics," delivered to the Engineering Alumni Association of the University of Kansas.

In 1917, a paper on "The Economics of Steel Arch Bridges," presented to the American Society of Civil Engineers, published in its "Proceedings," and awarded its Norman Medal.

In 1918, a paper entitled "Comparative Economics of Cantilever and Suspension Bridges," presented to the Western Society of Engineers and published in its "Proceedings."

In 1919, a paper on "Economic Span-Lengths for Simple Truss Bridges on Various Types of Foundation," presented to the last-mentioned society and published in its "Proceedings."

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