The term Jacob's staff is used to refer to several things, also known as cross-staff, a ballastella, a fore-staff, a ballestilla, or a balestilha. In its most basic form, a Jacob's staff is a stick or pole with length markings; most staffs are much more complicated than that, and usually contain a number of measurement and stabilization features.

Our WK-19-1400 Jacob staff measures 54 inches in height and weighs less than four pounds. Crafted from quality maple wood, you can use this staff with our foresters compass, surveyor’s compass or any other compass or instruments designed for mono pole operation. Of course, in some cases, you might prefer to use a tripod instead of our Jacob staff.

The original Jacob's staff, or cross-staff, was a single pole device credited to Levi ben Gerson (1288-1344), who was one of the leading Jewish mathematicians of the 14th century. The pole was marked in degrees, and the altitude of the stars could be determined by using a sliding wooden panel on the rod.

The cross-staff was a navigational tool used to measure the angle between the horizon and a celestial body such as the sun or stars. By knowing this angle, a navigator could then determine his latitude and direction. The cross-staff is also referred to as the fore-staff and the Jacob’s staff.

2014年3月31日 · It is actually a cross staff (or "Jacob's staff"), a tool widely used by astronomers and navigators before the invention of the telescope, and for a while afterwards. It consists of a main staff with a perpendicular crosspiece, attached at its middle to the staff and able to slide up and down along it.

2016年7月8日 · One of the simplest and most useful tools in geology is the Jacob staff. More robust than a tape measure or meter stick, the Jacob staff is used to measure bed thicknesses on an outcrop. The staff is usually 1.0-1.5 m and solid enough to be held perpendicular to bedding in areas of steep dip without collapsing or bending.

Have you seen a modern surveyor using a single vertical rod with an instrument on top to measure property lines? That pole is nicknamed a "Jacob's Staff." Hundreds of years ago, however, the term "Jacob's Staff" was used to refer to more than one type of instrument; it's the other instrument that I want to discuss today.

When you hear the term Jacob (or Jacob's) staff, you probably have a mental image of a single pole used to support a compass. However, the original Jacob staff was actually a surveying instrument developed in the 1300's that was used in making nautical and astronomical meas­ urements. The original Jacob staff, or cross-staff, was a

2013年2月11日 · Jacob's Staff was invented in the 13th century as an aid in finding heights and distances. It was not until the 15th century that the German scientist Johannes Mueller popularized the instrument. This was the age when the Europeans began exploring beyond the Mediterranean Sea.

2024年9月27日 · Jacob 's staff (plural Jacob's staffs) A single straight rod or staff, pointed and iron-shod at the bottom, for penetrating the ground, and having a socket joint at the top, used, instead of a tripod, for supporting a compass. Verbascum thapsus, the common mullein.