420 eepoet — 1878. 



the facts which, they have observed. And, indeed, the mere fact of the 

 trials having been undertaken shows that the importance of the effect of 

 the reversed screw on the steering while the ship is stopping herself is 

 beginning to be recognised. This is further shown by the fact that one 

 of the trials was undertaken at the instance of the Court of Mr. Stipen- 

 diary Yorke, in order to ascertain if the captain of the s.s. Tabor had been 

 justified in starboarding his helm in order to bring his vessel round to 

 starboard after his screw was reversed. 



All these trials, without a single exception, confirm the results 

 obtained in the previous trials made by the Committee. But this is not 

 the most important purpose which this year's trials serve. For, as re- 

 gards the general effect of the reversed screw on the action of the rudder, 

 the trials already, reported, particularly those of the Hankoiv (see last 

 year's Report, p. 201), are conclusive, and leave nothing to be desired. But 

 the previous trials were all made with fast vessels at their full draught, their 

 screws being well covered, and the conditions of the weather being most 

 favourable. The trials this year, on the other hand, appear, for the most 

 part, to have been made with vessels in light trim ; and in two instances 

 the wind was blowing with considerable force. The result of these cir- 

 cumstances on the behaviour of the vessels is very decided, and coincides 

 remarkably with the effects deduced by Professor Reynolds from his 

 experiments on models (see Report 1875, i., p. 145), viz., that when the 

 screw is not deeply immersed and froths the water, it exerts, when reversed, 

 considerable influence to turn the vessel independently of the rudder; 

 the vessel turning to starboard or port, according as the screw is right or 

 left handed, which effect (and this seems to be the point most generally 

 unknown) nearly disappears when the screw is so deeply immersed that 

 it does not churn air with the water. 



Neither the Admiralty, the Board of Trade, nor the Elder Brethren 

 of Trinity House have taken any further notice of the results communi- 

 cated to them by the Committee. 



The Marine Board of South Shields has, however, taken considerable 

 interest in the question, has invited captains to make trials, and Mr. J. 

 Gillie, the Secretary, was present at the trial of the Tabor ordered by 

 the Court, and reported the results to the Committee. 



There have been numerous collisions during the year. In almost all cases 

 the practice of reversing the screw has been adhered to. In many, if not 

 in all instances where this has been done, the evidence goes to show that 

 the vessel in which the screw was reversed did not turn in the direction 

 in which those in charge of her were endeavouring to turn her. In two 

 important cases this fact was fully apparent even to those in charge of 

 the vessel. And in one instance the owners and captain of the vessel 

 attributed the failure to steer to its true cause, namely, the reversal of 

 the screw ; although in both cases those immediately in charge of the 

 vessels contended that the rudder was not handled according to their 

 directions. 



The first case was that of the Menelaus and the Pilot schooner 

 on the Mersey. The Menelaus was in charge of a first-class pilot, and 

 this steamer, in broad daylight, ran into and sank the Pilot schooner, 

 which was dropping up the river with the tide. The pilot in charge con- 

 tended that, owing to the wheel chains having got jammed, his orders 

 were not attended to. The jamming of the chains was denied by the 

 owners, and the fact that they subpoenaed the Secretary of the Committee 



