Sextant

user notice: The _custom_breadcrumbs_get_breadcrumb() function called token replacement with an array rather than a string for $text in /home/drupal6/sites/all/modules/token/token.module on line 263.
user notice: The _custom_breadcrumbs_get_breadcrumb() function called token replacement with an array rather than a string for $text in /home/drupal6/sites/all/modules/token/token.module on line 263.

Inventory Number:

AST11

The sextant consists of a triangular frame, an index arm which can be moved across the bottom arced limb, two sights and two reflecting mirrors. One mirror is moved with the arm, and the other (half of which is transparent) is fixed to one limb. One sight is fixed below this mirror and the other on the opposite limb. The arc of the bottom limb is 60degrees and a venier scale on the index arm allows for more accurate reading.

Functioning:
An altitude-measuring device. It is based on the principle of light reflection and angles of incidence as the octant, but it has the capability to record over 120 degrees of arc, while having an actual arc of 1/6 of a circle.

Data

Date:

19th century

Materials:

Iron, Brass

Location:

D. Polemis Collection, Island of Andros

Dimensions:

Length : 22cm, Heigth : 24cm