on the telephone

*on the telephone

 and *on the phone
Fig. speaking on the telephone. (*Typically: be ~; get ~.) She's on the phone but won't be long. Please take a seat while I'm on the phone. Get on the phone and call him back immediately!
See also: on, telephone
References in classic literature ?
On getting out of bed that morning he had fully made up his mind to ignore what had been said the night before; he had been convinced, by the sight of Denham, that his love for Katharine was passionate, and when he addressed her early that morning on the telephone, he had meant his cheerful but authoritative tones to convey to her the fact that, after a night of madness, they were as indissolubly engaged as ever.
A Mr Morrison,' sad Annette, indifferently, 'rang up on the telephone and asked me to tell you that he was greatly worried by the piles of music which were littering the rooms you lent him.