Description and Notes:
These small set squares (the height of the 60 degree one is about six inches) appear to be made of maple with boxwood frame and figure eight inlaid joints. Although the two were constructed in the identical manner, but they are in fact not a set. Not only because they were acquired from different sources, but also the 45 degree one is thicker than the 60 degree one. Besides, the 45 degree one is signed E&S and marked with a number 252, whereas the other only marked with a number 373.
The construction of these set squares is similar to the ones devised by W. F. Stanley, and which was highly prised by him in his book (p. 183) as:
Framed set squares ... are the best kinds of set squares for large or moderately large sizes, or for use in hot climates. They are generally made of mahogany, and edged with ebony. Although made of wood, it is in such narrow strips that the contraction of the fiber is inconsiderable. These set squares also retain their angle very correctly, from the fact of the grain of the wood running longitudinally on all sides. Being open in the centre is also an advantage, making the set square lighter, and obscuring less of the surface of the drawing than the solid form. They require very careful workmanship; the angles should fit perfectly, and be united with a tongue of metal which should be riveted through to the surface; made thus, the angles will be as strong as the sides.