Accession No

0531

Brief Description

spectacles, double, temple, 1850 (c)

Origin

Maker

Class

optical

Earliest Date

1850

Latest Date

1850

Inscription Date

Material

organic (tortoise shell); glass; cloth (velvet)

Dimensions

length 118mm; breadth 30mm

Special Collection

Robert Whipple collection

Provenance

Purchased from T.H. Court on 28/05/1927.

Inscription

Description Notes

Tortoise shell. Round frames with second lenses (hinged) to the side. Wide c-bridge straight side pieces. (Lenses missing). Velvet padding on side pieces.

Condition: fair; incomplete (lenses missing).

References

Events

Description
Spectacles
Usually consisting of a pair of lenses held in a frame, spectacles may have originated in the ancient civilizations of China and the Mediterranean, but early forms were crude. It was only in the 18th century that the grinding of lenses became sufficiently advanced to make then really effective for correcting sight defects. In order to correct for near sightedness, the lenses must be concave, which diverges the rays of light (angles them apart), and for long sightedness they must be convex, to angle the rays of light together.

Spectacles are not solely used for defective eyesight; the Inuit and the Yupik use wooden spectacles with very small slits in them to reduce the glare from snow and ice.

FM:42585