A Predecessor of the Sextant
Already Christopher Columbus was using this ingenious instrument to measure the declination of stars and angular distances of landmarks.
The Jacob's Staff served navigators reliably for a long time before it was superseded by the mirror sextant in the 18th century. This historically accurate, fully functional cardboard replica has a main staff with scales that can be read to one minute accuracy and has 3 transoms that range from 8°, 15°, and 29° to 45°.
This is how to measure angles
Push a transom onto the main staff and place its flat end under the eye on the cheekbone. Slide the transom back and forth until it fits snugly between the two points. If the angle is too small or too large, use a different transom. The angle is measured on the main bar, on the side of the transom facing your eye. Each transom has its own scale printed on the main staff.
For teachers and students
The Jacob's Staff is easy to build and makes excellent teaching material for secondary schools. Like all our Educational Kits, it can also be used for group and project work on the subjects of astronomy and physics.
3x A4 printed cut-out cardboard sheet
Detailed English instructions included
Dimensions: 57 x 28 cm
Producer: AstroMedia GmbH, Im Wirrigen 30, 45731 Waltrop, Germany, astromedia.de
Below you can download the instructions for this kit.
Things you’ll need for assembly, or which might be useful:
- a sturdy, flat work surface. A cutting mat, for example, is useful
- a ruler
- a pair of scissors
- a craft knife or scalpel
- a blunt knife or a bone folder
- a good all-purpose glue
Adult supervision:
Children should use the kit under adult supervision to avoid risks arising from improper handling.
Risk of injury:
Take particular care when handling pointed and sharp parts! Use sharp tools with care and, where necessary, take appropriate safety precautions to avoid injury.
Fire hazard:
Keep away from open flames and sources of heat. The product contains highly flammable materials.
Use of adhesives:
When using adhesives, follow the manufacturer’s safety instructions. Work in well-ventilated areas and avoid contact with the skin or eyes.
