Professor Jenkin has contributed several valuable papers to our Transactions.

In 1869 we had “The Practical Application of Reciprocal Figures to the Calculation of Strains on Framework,” in which he exemplified in a very clear manner the mode of applying to important statical questions a beautiful principle, due in part to Rankine but mainly to Clerk-Maxwell.

The paper for which the award of the Keith Prize is now made is more thoroughly original, and may be roughly described as an extension of Maxwell's principle to the kinetics of machinery, where all parts move in one plane. It is entitled “The Application of Graphic Methods to the Determination of the Efficiency of Machinery.” The first part was read to the Society in 1877, and the second in the following year. All three of these papers are in our Transactions.