🌐EnglishEnglishBahasa IndonesiaDeutschEspañolFrançaisItalianoNederlandsPolskiPortuguêsSvenskaРусскийالعربية한국어中文日本語EntityQ843239· pop 26· linked from 122 articlesJacob's staffcalibrated wooden rod with sliding crosspiece used for measuring the altitude of celestial bodies or the height of distant objectsConnectionsSunConceptastronomyEntityCategories14th-century inventionsAngle measuring instrumentsCelestial navigationHistory of astronomyJacobNavigational equipmentObsolete scientific instrumentsScience and technology of the Song dynastySurveying instruments