Finding an old notice on a canal towpath inspired a consultation with colleagues and search for evidence in an old book to help people look into how the words and symbols used in the teaching of electricity have evolved, including the apparent oddity of the symbol "I" for current. It is easy to explain that people use the symbol "Q" for what is now called electric charge. The original concept was considered for electrostatics and was described as the quantity of electricity. Use of the letter "I" for current is a little harder to explain. However, one has to realise that, in the initial efforts to understand these ideas, scientists would find analogies with what was already established. (Contains 1 figure.)