V 



sequently went on the experimental cruizes of Her Majesty's ship 

 " Devastation," when valuable observations were made on her rolling 

 and general behaviour at sea. 



His services as a member of the " Inflexible " Committee in 1877, 

 were the latest practical application of his studies of the rolling 

 question. 



Another outcome of the Committee on Designs was an important 

 experiment on the resistance of a full sized ship which was conducted 

 under Froude's superintendence. 



The " Greyhound," a corvette, was towed at various speeds, and her 

 resistance measured by a special dynamometer. The result was 

 valuable as verifying the result of the experiments with models, and 

 it was also valuable as calling attention to the great difference be- 

 tween the power delivered in a ship's engines, and the power usefully 

 employed in propelling the ship. 



The causes of this difference, especially that of the detrimental 

 action of the screw propeller, when placed immediately behind the 

 ship, was a matter to which Froude paid great attention, and the 

 several ways in which the engine power is used or wasted, was the 

 subject of one of his later papers read before the Institute of JSTaval 

 Architects. 



At the establishment at Torquay there have been in progress a 

 series of experiments in the forms of ships from which valuable 

 general results have already been obtained, and for the Royal Navy all 

 the proportions and forms have been subjected to the investigation 

 given by Froude's experimental apparatus at Torquay. 



In 1875, as President of the Mechanical Section of the British 

 Association, Froude, in his address explained in an intelligible form 

 the bearing of the stream line theory on the question of the resistance 

 of ships. This address he afterwards delivered as a lecture at the 

 Royal Institution. 



It has been said above that propulsion was a subject carefully con- 

 sidered by Froude. In connexion therewith, he was requested by the 

 Admiralty to design a dynamometer, capable of testing the power 

 delivered by large marine engines. The novel and ingenious instru- 

 ments he thought out to meet the extreme conditions of transferring 

 to a resisting lever the rotative force of 2,000 or 3,000 horse-power 

 was described by him at the meeting of the Institution of Mechanical 

 Engineers, at Bristol, in 1877. 



He also had occasion to investigate the elementary principles de- 

 termining the proportion of screw propellers : and his paper on this 

 subject, read at the meeting of the Institute of Naval Architects in 

 1878, was the last of his published contributions to science. 



Froude's investigations had been recognised by his election, in 1870, 

 as a Fellow of the Royal Society, and by his receiving in 1876 the 



