dry compass

Dry compass were invented in the Mediterranean around 1300.

In the early modern period, dry compasses were suspended in gimbals.

In dry compasses, the needle movement is unstable and cannot be relied upon for accurate bearings.

The dry compass was invented around 1300 by Italian inventor Flavio Gioja.

In 1282, the properties of magnets and the dry compass were discussed by Al-Ashraf, a Yemeni physicist, astronomer, and geographer.

The familiar mariner's dry compass which uses a pivoting needle suspended above a compass-card in a glass box is invented in medieval Europe no later than 1300.

In navigation, the foundation to the subsequent age of exploration was laid by the introduction of pintle-and-gudgeon rudders, lateen sails, the dry compass, the horseshoe and the astrolabe.

His work is particularly noted for containing the earliest detailed discussion of freely pivoting compass needles, a fundamental component of the dry compass soon to appear in medieval navigation.

In 1300, an Arabic treatise written by the Egyptian astronomer and muezzin Ibn Simʿūn describes a dry compass for use as a "Qibla indicator" to find the direction to Mecca.

According to Needham, the Chinese in the Song Dynasty and continuing Yuan Dynasty did make use of a dry compass, although this type never became as widely used in China as the wet compass.

Along with new navigational techniques such as the dry compass, the Jacob's staff and the astrolabe, these allowed economic and military control of the seas adjacent to Europe and enabled the global navigational achievements of the dawning Age of Exploration.

The dry compass used in China was a dry suspension compass, a wooden frame crafted in the shape of a turtle hung upside down by a board, with the lodestone sealed in by wax, and if rotated, the needle at the tail would always point in the northern cardinal direction.

In 1269, Pierre de Maricourt (commonly referred to as Petrus Peregrinus) wrote a letter to a friend in which he described two kinds of compass, one in which an oval lodestone floated in a bowl of water, and the first dry compass with the needle mounted on a pivot.

Although the 14th-century European compass-card in box frame and dry pivot needle was adopted in China after its use was taken by Japanese pirates in the 16th century (who had in turn learned of it from Europeans), the Chinese design of the suspended dry compass persisted in use well into the 18th century.