John Samuel Enys
John Samuel Enys ( 21 September 1796 – 29 May 1872 ) was a British mining engineer and scientist who wrote several important papers on the "duty" of steam engines and other types of power delivery , from water wheels to horses . 
<triplet> John Samuel Enys <subj> 21 September 1796 <obj> date of birth <subj> 29 May 1872 <obj> date of death