Joseph McKenna, Looney v. Metropolitan Railroad Company…
“ A witness who had experience with the construction of electric railway systems, and was familiar with the action of electricity generally, and had experience in superintending the work of disconnecting a plow from an electric car and adjusting the wires to move an overhead system, testified that, in his opinion as an expert, it would be the duty of a conductor to keep the trolley off the wire until he received some signal from the man beneath the car. ”
