Obituary Notices. 
xxi 
was shown in Edinburgh, and attracted Sang’s attention. He went 
into a consideration of the subject, and made the discovery that 
every wire, no matter what may be the form of the hole through 
which it has been drawn, has one direction in which the flexibility 
is greatest, and another, at right angles, in which the flexibility is 
least. He tells that he was startled by finding that theory led him 
to believe that, if the rapidity of vibrations in the one direction be 
double of that in the other, the common parabola should be the 
result. He then drew out curves according to theory, and manu- 
factured wires of the proper proportions as indicated by the theory, 
and found a perfect coincidence between the actual and computed 
phenomena. In 1831 he exhibited before the Royal Scottish 
Society of Arts these wires, with their silver knobs, and the beauty 
of the curves was much admired. They never ceased to charm 
him, and he often brought them out to show to friends. In 1889, 
after a lapse of fifty-eight years, he again brought the subject before 
the Society of Arts, and exhibited a new set of wires he had 
recently made. In 1838 he read a paper to the Society of Arts, 
describing a Dioptric Light erected at Kirkcaldy, and he also gave 
a description and exhibited drawings of the apparatus he used for 
cutting the annular lens to' the true optical figure. For that paper 
he was awarded the Keith Medal, value 20 sovereigns. In pre- 
senting the medal, Sir John Graham Dalziel stated that “no 
opportunity had hitherto occurred since the Keith fund came into 
the possession of the Society for awarding that prize. How, how- 
ever, it was highly gratifying to find one of the most scientific, 
useful, and meritorious of all who had been connected with the 
Society, Mr Edward Sang, entitled to this eminent distinction. 
His skill, his labours and unremitting exertions in various scientific 
departments, were too well known to be embellished by any com- 
mentary.” In 1810 he was presented with the Society of Arts 
Silver Medal, value 10 sovereigns, for his papers on the “ Construc- 
tion' of Circular Signal Towers,” on the “Effects of the Curvature 
of Railways,” and for his valuable essays on Life Assurance. For a 
period of several years he lectured on Natural Philosophy, and in 
1841 he became Professor of Mechanical Science in the Manchester 
Hew College. Shortly after, he went to Constantinople to assist in 
establishing schools of civil engineering, and in laying out railroads 
