Editing Opisometer (section)

== History of the opisometer ==
Early versions of this instrument were [[patent]]ed in 1873 by the English engineer Edward Russell Morris.<ref>[http://www.london-gazette.co.uk/issues/24044/pages/5837/page.pdf THE LONDON GAZETTE, DECEMBER 12, 1873]</ref> The instruments he produced were initially described as a ''Patent Chartometer'' although later versions were sold under the curious name of ''Wealemefna''.<ref>[http://www.mathsinstruments.me.uk/page71.html Mathematical Instruments: Map Measurers]</ref> Writing in 1881, Morris described how he had created a wholly original name in an attempt to outwit his imitators; he also refused to disclose the origin of the word.<ref>English Mechanic and World of Science: Vol. 33, London, 1881</ref>