There could not have been a more fortunate beginning, with clear weather and a calm sea, and the wind in exactly the right quarter.

On Saturday and Sunday the same conditions held, so there was time and opportunity for the three very miscellaneous ships' companies to shake down into something like order, and for all the elaborate discipline of sea life to be arranged and established; and we may employ the interval by noting what aids to navigation Columbus had at his disposal.
The chief instrument was the astrolabe, which was an improvement on the primitive quadrant then in use for taking the altitude of the sun.

The astrolabe, it will be remembered, had been greatly improved, by Martin Behaim and the Portuguese Commission in 1840--[1440 D.W.]; and it was this instrument, a simplification of the astrolabe used in astronomy ashore, that Columbus chiefly used in getting his solar altitudes.

As will be seen from the illustration, its broad principle was that of a metal circle with a graduated circumference and two arms pivoted in the centre.

It was made as heavy as possible; and in using it the observer sat on deck with his back against the mainmast and with his left hand held up the instrument by the ring at the top.