This research is in the document and information gathering stage
The patent we are looking at: (English/UK) Patent Number 329, 1858 February 20th "Thomson's Improvements in Testing and Working Electric Telegraphs"
Physical copy: http://special.lib.gla.ac.uk/manuscripts/search/detail_c.cfm?ID=94776
Best online source so far: "English Patents of Inventions, Specifications, 1858, 317 - 399" Page 62 (in the PDF) https://books.google.ca/books?id=uOJg2EbSJ5EC&lpg=RA38-PA1&ots=Btc_iV27DI&dq=English%20Patents%20of%20Inventions%2C%20Specifications%2C%201858%2C%20317%20-%20399&pg=RA5-PA1#v=onepage&q&f=false
Mention in "The life of William Thomson, baron Kelvin of Largs" Vol. 1, page 381 https://archive.org/details/lifeofwillthom01thomrich/page/n381