# Royal Naval Biography/Pearse, John

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JOHN PEARSE, Esq. [Commander.]
Was made a lieutenant on the 29th Dec. 1800; and served for several years as first of the Cruiser sloop, one of the most active and successful cruisers on the North Sea station, where she was successively commanded by Captains John Hancock and Pringle Stoddart.
On the 24th April, 1810, Lieutenant Pearse was appointed to the command of thee Decey cutter, which vessel he appears to have paid off in June 1814. We next find him commanding the Wickham revenue cruiser, in 1817. He obtained his present rank, “for long and active services,” May 27th, 1825.
This officer is the author of an article in the “United Service Journal,” for Aug. 1830, entitled, “Observations on the present Distribution of Weight and Pressure in, Ships of War.” The following is taken from the “Devonport Telegraph,” Sept. 7th, 1833:–
“Masting of Ships. – A discovery, which is likely to be attended with important results to the navy, has recently been made by Commander John Pearse, R.N., of Plymouth, after a series of delicate and laborious experiments, in which the point, according to the opinion of those most conversant with such subjects, who have had an opportunity of examining these experiments, has been fully demonstrated. This officer, from various circumstances, and, among other things, the imperfect systems of the principle of masting ships, was led to doubt that the centre of gravity of a ship was the axis of rotation, as hitherto imagined, ​and that this was the cause of so many errors occurring in masting. He accordingly proceeded to ascertain the truth of his doubts by experiments on different models, which he has continued for upwards of twelve months past, and which have been so correctly made, so strictly consistent with the laws of mechanics, and have proved so satisfactory, that the Admiralty have been made acquainted with the whole of the facts and results, and which, we understand, cannot fail to render the science of shipbuilding more comprehensive and demonstrative, as well as lead to the correction of other errors in the theory equally worthy of consideration. It is not in the province of a newspaper to discuss scientifically points of mechanical interest, but the importance of a discovery of this nature will be easily understood by all nautical men, and especially by those who know any thing of naval architecture. It is a new fact in science, and practically useful in a valuable art allied to our national glories, and is therefore doubly interesting. The axis of rotation has been fixed by Captain Pearse’s experiments at some distance above the centre of gravity of the ship, and in the point which is known by the name of the metacentre; and we understand he considers the complexity of the theory, and not having considered the subject in a sufficiently practical shape, to have led authors into the error of confounding the centre of gravity of the ship with the axis of rotation; and that this has led to the error of supposing the lateral effort of the water, or resistance to lee-way, to produce effects contrary to truth, and from which proceeds the present imperfect system of masting. In fact, the discovery of the true axis of rotation will be a complete key to the improvement of naval architecture, as all the forces, which are so constantly and variously acting, are estimated by the distances from the axis of rotation to the points where they are applied.”