Page:Royal Naval Biography Marshall v3p1.djvu/88

 In 1817, Captain Phillips submitted to the Admiralty a plan for propelling ships by the capstan; and, in 1819, another, for increasing the power of that machine by wheel-work, which was the basis of the improved capstan now bearing his name, and for which he has a patent. The following extracts are taken from his recently printed explanation and description of this very valuable invention:–

“The experience of ten years, the period since Captain Phillips’s capstan was first introduced into His Majesty’s service, has enabled him to submit three several plans of improved capstans, founded upon his first invention, engravings of which are attached. His arrangement of wheel-work produces a greater power with the same proportioned wheels than any he has ever seen, as the power gained by the difference of diameter between the first and last wheel is always increased equal to an entire revolution of the first mover; the series of wheels may in consequence be of less diameter than in any other arrangement, and necessarily lighter. This additional power is gained by fixing the exterior wheel, and communicating the effect so produced to the capstan, by bolts fixed to, or withdrawn from, the frame that carries the centre of the intermediate pinions.

“Whenever it is necessary to use a greater power than the leverage of the bars produces in the simple capstan, a resource is found in tackles; but they are not continuous, very long in application, and very difficult to be removed, particularly when surges take place: with Captain Phillips’s capstan, on the contrary, the application of the power is immediate, it is subject to no difficulty in removal, and continues its motion as long as may be required; whereas the motion of the tackle can but continue until the two blocks come together. The power capstan is as strong as the plain capstan, therefore there can be no risk in using it; and it does not follow that the power is to be applied on all occasions, more than that recourse should be had to tackles in every trifling difficulty; but it is highly advantageous that, when great obstacles are to be overcome, such a power should be always at hand, and capable of being applied, in the darkest night, in less than a minute; and as a proof that it has been of material benefit in an extreme case of difficulty, it is but to quote the words of Captain Parry, at the court-martial held upon the officers of the Fury, for the wreck of that ship, where he distinctly stated, that, but for Phillips’s capstan, the expedition must have remained another winter in the ice.

“The advantages and peculiarities of these capstans are, that although used with different powers; both capstans traverse the same way, either as a common or increased power capstan; and that the people are never obliged to turn themselves at the bars, and to heave the other way, when a different power is applied, and in so doing to leave the capstan entirely dependent upon the pauls; but the capstan is, under all circumstances,