290 Mr. Napier on Water-tight Compartments in Iron Vessels. 



her voyage and discharged her cargo at Glasgow as if nothing had 

 happened. The foremost compartment in this case, however, was very 

 small, as an additional water-tight bulkhead had been placed near the 

 stern, in order to make a fourth compartment. On a subsequent occasion 

 this steamer was herself struck amidships by a sailing vessel off the south 

 of England, but she did not sink till about three hours after the accident, 

 though the centre compartment filled immediately. 



Many other instances might be mentioned ; the most remarkable case 

 with which I am acquainted is that of the " Thistle '' steamer, a vessel, 

 which after striking the rocks on the North of Ireland, steamed without 

 assistance thence to Greenock, a distance of about seventy nautical mile?, 

 across the North Channel, with the fore-deck under water, the fore and 

 after compartments filled with water, and nothing but the centre or 

 engine compartment free. She arrived in other respects safely at her 

 destination. 



The accompanying letter from the managers of the vessel, gives the 

 particulars of the accident, and the sketches taken partly from the vessel 

 while repairing, and partly from the original designs and from information 

 received from those on board during the accident, show very correctly 

 the appearance she presented on arriving at Greenock, and also the 

 injuries the bottom sustained upon the rocks. 



If it were necessary to lengthen this paper many other examples might 

 be given, but the preceding show that water-tight bulkheads of sufficient 

 strength have been the means of saving both lives and property. 



Care, however, must be taken in endeavouring to make strong bulk- 

 heads water-tight, not to weaken materially the general strength of the 

 ship by piercing the shell plates with too many holes in a line. 



From the descriptions given at the time of the loss of H.M.S. " Birken- 

 head " off the south coast of Africa, it appeared that her sudden breaking 

 up must have been owing to this cause. 



"Glasgow, 11th March, 1852. 

 " Robert Napier, Esq. 

 "Dear Sir, — You have no doubt heard of the accident to 'Thistle ' 

 steamer, on the evening of Saturday last, while proceeding along the 

 north coast of Ireland in a fog. She struck on some sunken rocks, and 

 stove in part of the bottom plates both forward and aft. The fore-hold, 

 after-hold, and cabins filled, but fortunately the middle compartment, 

 forming the engine and boiler space, remained uninjured. And after 

 she was floated off the rock the bulkheads both before and abaft the 

 engine space stood firm, and she returned to Greenock by the power of 

 her own engines alone, without assistance from any other vessel, though 

 solicited by two steam vessels to allow them to assist. The fact of a 

 vessel of her tonnage (670 tons) steaming across the Irish Channel 

 safely with her holds and cabins full of water, the mid compartment of 

 the vessel only keeping free, is most remarkable, and a strong testimony 

 to the value of water-tight bulkheads. 



