chronometrical

At the age of 25 he employed his whole time in chronometrical improvements.

It is my intention to be at Port Famine by the 1st of April, and at Rio de Janeiro by the 1st June, calling in my way at Monte Video, or Gorriti, for chronometrical observations; and if can, conveniently, I shall also go to Port Desire for the same purpose.

On the 4th, being about one hundred miles to the N.E. of Cape Blanco, I communicated with Captain Stokes, and gave him directions to proceed to Port Desire for chronometrical observations, and then follow me immediately to Cape Fairweather or Cape Virgins.

I was again disappointed, and very reluctantly left Rio de Janeiro, on the 16th, for Monte Video; but that I might still benefit by the orders which were sure to be in the following packet, I determined upon calling at Santos, and St. Catherine's, for chronometrical observations; leaving the Beagle to wait for letters conveying the decision of his Royal Highness the Lord High Admiral.

Having obtained good chronometer sights in the afternoon, we steered on through the night, intending to pass to the westward of the Archimedes Shoal; which would have been rather a rash step, had we not been well assured of the correctness of our chronometrical reckoning.