ltwilliammowett:This pocket compass and clinometer was specially made for Charles Darwin for his HMS
ltwilliammowett:This pocket compass and clinometer was specially made for Charles Darwin for his HMS Beagle voyage. The clinometer was used to measure the gradients of rock formations, making this a vital piece of geological equipment. William Cary’s workshop in London was well known for the quality of the scientific instruments it produced. This piece is enclosed in a fine mahogany box.made c. 1831 -- source link