Obituary Notices. 
xxv 
a committee, which reported most favourably upon it, stating 
that “ the author deserved great credit for the analytical skill and 
ingenuity he had displayed in the investigation, which must have 
cost him much thought and great labour in computing from their 
equations, and tracing a large number of curves, in order to obtain 
the requisite familiarity with the use of the formulae, and also for the 
purpose of constructing the model which was shown.” This paper 
was awarded the highest prize the Society could give, viz., the 
Keith Prize, value 30 sovereigns. On the 8th December 1873 
he read a paper giving a description of a new machine for the hand- 
spinning of rope yarn. The machine was shown in action, and the 
work performed by its beautiful compound motion was much 
admired. Any length of rope could be spun without having 
recourse to the long rope-walks commonly used. In 1886 this 
Society presented him with the Macdougall-Brisbane Prize for 
1882-84 for his paper “On the Need for Decimal Sub-Divisions in 
Astronomy and Navigation, and on Tables therefor.” 
Our learned Fellow, Lord McLaren, who was in the chair, in 
making the presentation, said that “ Dr Sang’s paper covers a wide 
range of inquiry, embracing various branches of pure mathematics, 
mechanics, and optics, as well as the applications of these sciences 
to practical astronomy, chronometry, and naval architecture. No 
considerations, save zeal for the advancement of science and a 
benevolent desire to lighten the labours of future computors, could 
have induced Dr Sang to undertake such a gigantic task, or 
have sustained him through the wearisome mass of mechanical 
detail which overlaid the more interesting parts of his occupation.” 
Time will not permit of noticing more of his work, a fraction of 
which has only been touched upon, but enough to show what the 
man was and what he did. Everything he gave his mind to as a 
philosopher was undertaken with an honest, conscientious, and 
single-minded devotion to science ; and everything he put his 
hand to as a craftsman was marked with a beauty of design, a 
faultless precision and delicacy of finish, of which the most skilled 
workman might be proud. It may be added that accuracy in 
workmanship was insisted on by him to an extent that to many in 
times past seemed useless. In this he surely anticipated what was 
coming, for the marvellous development of automatic machinery — 
