24 Gee, Daltoris Lectures and Lecture Illustrations. 



Sheet 8. 



(22"x32".) Illustrates the simple pendulum. Two 

 pendulums are shown vibrating through the same angle. 

 Ratio of length of pendulums are as 1:4. 



Sheet 9. 



(2i"xi7".) Compares the rates of efflux of water 

 from the same head of water with five different kinds of 

 jets. 



Sheets 11 to 21. 



These are copied with some modifications from Peter 

 Ewart's paper on "Moving Force." 9 



Peter Ewart was elected a member of the Literary 

 and Philosophical Society in 1798, and for 22 years was 

 a Vice-President. In 1835 he became the Chief Engineer 

 and Inspector of Machinery in the Government Dock- 

 yards at Woolwich. In writing- his paper on " Moving 

 Force " he was assisted by Dalton, who suggested some 

 of the experiments described. In his Royal Institution 

 Lectures in 1909-10 Dalton tells us " that several have 

 been wonderfully struck with Mr. Ewart's doctrine of 

 Mechanical Force." Part I. of Vol. II. of " The New 

 System of Chemical Philosophy" (1827) is dedicated to 



John Sharpe, Esq., F.R.S., 



and to 



Peter Ewart, Esq., 



Vice-President of the Literary and Philosophical Society 

 of Manchester, " on the score of friendship, but more 

 especially for the able exposition and excellent illustra- 



See Manchester Memoirs, 2, 2nd Series, p. 105. Also see " Some 

 Account of the late Mr. Ewart's Paper on the Measure of Moving Force," 

 by Eaton Ilodgkinson, Memoirs, 12, p, 138 ; also an account of the same 

 by J. Bottomley, in the " Centenary of Science in Manchester," by R. 

 Angus Smith, p. 246. 



