Early telephone by Alexander Graham Bell, 1877.

This form of magnetic telephone, patented by Alexander Graham Bell (1847-1922), was one of the first to be brought into practical use, and demonstrates the transition from his early experimental telephones to a more practical one. It was sometimes called a 'box' telephone, due to the shape of the cover which normally protected the magnet and coils. It was the first telephone to use a permanent magnet, which avoided the need for a battery. The small horn could be used as both a mouthpiece and an earpiece. It was used at the Lloyds Signal Station in Cornwall. A large instrument of this type was also used during a demonstration at the Essex Institute, Salem, Mass., on 12 February 1877. The sounds reproduced by it were sufficiently loud to be audible to a large audience, the words having been shouted into a similar instrument in Boston, 26 km away.

Small, hollow wooden cylinder to connect the mouth or ear piece for an early Bell telephone instrument used at Lloyds station, patented by Alexander Graham Bell, unknown maker, British, 1906.

This form of magnetic telephone, patented by Alexander Graham Bell (1847-1922), was one of the first to be brought into practical use, and demonstrates the transition from his early experimental telephones to a more practical one. It was sometimes called a 'box' telephone, due to the shape of the cover which normally protected the magnet and coils. It was the first telephone to use a permanent magnet, which avoided the need for a battery. The small horn could be used as both a mouthpiece and an earpiece. It was used at the Lloyds Signal Station in Cornwall. A large instrument of this type was also used during a demonstration at the Essex Institute, Salem, Mass., on 12 February 1877. The sounds reproduced by it were sufficiently loud to be audible to a large audience, the words having been shouted into a similar instrument in Boston, 26 km away.

This form of magnetic telephone, patented by Alexander Graham Bell (1847-1922), was one of the first to be brought into practical use, and demonstrates the transition from his early experimental telephones to a more practical one. It was sometimes called a 'box' telephone, due to the shape of the cover which normally protected the magnet and coils. It was the first telephone to use a permanent magnet, which avoided the need for a battery. The small horn could be used as both a mouthpiece and an earpiece. It was used at the Lloyds Signal Station in Cornwall. A large instrument of this type was also used during a demonstration at the Essex Institute, Salem, Mass., on 12 February 1877. The sounds reproduced by it were sufficiently loud to be audible to a large audience, the words having been shouted into a similar instrument in Boston, 26 km away.