"Propelling machinery is of British design.

(c) The term "sailing vessel" means any vessel under sail provided that propelling machinery, if fitted, is not being used.

Machinery meant "propelling machinery".

During the first decade of the 20th century, the company succeeded becoming a leader in marine engineering technology with the development of the Brown-Curtis turbine, the propelling machinery chosen by the Royal Navy for many of its major warships.

Insofar as ships given out to contract are concerned (and the same is the case in regard to propelling machinery built by contract), the director of navy contracts plays no part, the professional business being conducted through the controller of the navy, who is advised thereon by the director of naval construction and the engineer-in-chief.