sighting tube उदाहरण वाक्य

Furthermore, Gerbert instructed Constantine that the north pole could be measured with the upper and lower sighting tubes, the Arctic Circle through another tube, the Tropic of Cancer through another tube, the equator through another tube, and the Tropic of Capricorn through another tube.
Gerbert instructed Constantine that, if doubtful of the position of the pole star, he should fix the sighting tube of the armillary sphere into position to view the star he suspected was it, and if the star did not move out of sight, it was thus the pole star.
The Abney level is a handheld surveying instrument developed in the 1870s that includes a sighting tube and inclinometer, arranged so that the surveyor may align the sighting tube ( and its crosshair ) with the reflection of the bubble in the spirit level of the inclinometer when the line of sight is at the angle set on the inclinometer.
The Abney level is a handheld surveying instrument developed in the 1870s that includes a sighting tube and inclinometer, arranged so that the surveyor may align the sighting tube ( and its crosshair ) with the reflection of the bubble in the spirit level of the inclinometer when the line of sight is at the angle set on the inclinometer.