258 SOCIETY NAVAL ARCHITECTS AND MARINE ENGINEERS. 



double bottom at that point. A well extending to the outer skin is, however, permitted at 

 the after end of the shaft tunnels of screw vessels. 



Article XXII. 



GOING ASTERN. 



Vessels shall have sufficient power for going astern to secure proper control of the 

 vessel in all circumstances. 



Article XXIII. 



AUXILIARY STEERING APPARATUS. 



Vessels shall be provided with an auxiliary steering apparatus, which, however, may be 

 of less power than the main apparatus, and need not be worked by steam or other mechan- 

 ical power. 



Article XXIV. 



INITIAL AND SUBSEQUENT SURVEYS OF VESSELS. 



Every vessel defined in Article 2 of the Convention shall be subjected at least to the 

 following surveys, as specified in detail in Article XXV below: 



(A) A survey before the vessel is put in service; 



(B) Periodical surveys once each year; and 



(C) Additional surveys, as occasion arises. 



Article XXV. 



The surveys referred to in the previous Article shall be carried out as follows : 



(A) The survey before the vessel is put in service shall include a complete inspection of 

 the hull, machinery, and equipments, including the outside of the vessel's bottom, and the 

 inside and outside of the boilers. 



This survey shall be such as to insure that the arrangements, material, and scantlings 

 of the hull, boilers, and their appurtenances, main and auxiliary machinery, life-saving appli- 

 ances and other equipments, fully comply with the requirements of this Convention and of 

 the detailed regulations promulgated by the Government of the contracting State to which 

 the vessel belongs for vessels of the service for which it is intended. The survey shall also 

 be such as to insure that the workmanship of all parts of the vessel and its equipments is in 

 all respects satisfactory. 



(B) The periodical survey shall include an inspection of the whole of the hull, boilers, 

 machinery, and equipments, including the outside of the vessel's bottom. The survey shall 

 be such as to insure that the vessel as regards the hull, boilers, and their appurtenances, 

 main and auxiliary machinery, life-saving appliances, and other equipments, is in satisfac- 

 tory condition and fit for the service for which it is intended, and that it complies with the 

 requirements of this Convention, and of the detailed regulations promulgated as a result 

 thereof by the Government of the State to which the vessel belongs. 



(C) A survey, either general or partial, according to the circumstances, shall be made 

 every time an accident occurs or a defect is discovered which affects the safety of the vessel 

 or the efficiency or completeness of its life-saving appliances or other equipment, or any 



