[Telephone operators.]

[Telephone operators.]

[People observing telephone operators.]

[District selector frame in a dial exchange.]

Communications, Telephone Exchange.

Communications, Telephone Exchange.

Telephone, New York Telephone Co. Exchanges.

Telephone, New York Telephone Co. Exchanges.

[General view of some of the dial equipment, Trafalgar Central Office.]

[Sender frames, dial equipment.]

Communications, Telephone Exchange.

Communications, Telephone Exchange.

Communications, Telephone Exchange.

Telephone, New York Telephone Co. Exchanges.

Communications, Telephone Exchange.

[New York City Telephone Exchange.]

[Overseas switchboard at 32 Avenue of the Americas.]

[Early types of switchboards.]

[Early types of switchboards, Old Spring Exchange.]

P. C. Knox