I think the error here may be the comma after "Magnetic"; Morse's telegraph system, e.g., was commonly known as "the electro-magnetic telegraph" (earlier, less successful, telegraph systems were electrical but not electromagnetic) and the first company that commercialized his invention was called the Magnetic Telegraph Company.

The effect of operating an electromagnet at a distance seems to have been thought of as "magnetic" more than "electrical"; see e.g. at http://supreme.justia.com/cases/federal/us/56/62/case.html comments from Morse and his contemporaries like "If I can succeed in working a magnet ten miles, I can go around the globe" and "The chief anxiety ... was to ascertain the utmost limits at which he, Morse, could work or move a lever by magnetic power".

It seems plausible to me that even by 1912 the term "magnetic telegraph" might have been in use to distinguish the electromagnetic telegraph from other earlier sorts of telegraph.

(Note 1: the above is based on a small amount of web searching and may be full of errors. Note 2: it appears that in fact other people developed electromagnetic telegraphs before Morse -- e.g., a chap called Schilling in Russia in 1832 -- but Morse is the one commonly thought of as inventing it, and is surely the answer the examiners were looking for.)

the insane clown posse? http://www.youtube.com/watch?v=_-agl0pOQfs