MECHANICAL AND USEFUL ARTS. 43 



what would be required for a vessel of the magnitude we have 

 been considering. To secure a proportionate resisting power in 

 the deck, we shall require the arrangement, giving an area of 

 750 square inches, exclusive of the hatchways, which I have esti- 

 mated at eight feet wide. This sectional area would be distri- 

 buted as follows : — 



Total area of bottom ... 761-25 



"Thus we should have in the hull and deck a maximum area of 

 security, and the vessel, so far as regards her ultimate strength, 

 would be superior to any tests to which she might be subjected at 

 sea or on shore. Under the most trying circumstances she would 

 never break up, and the passengers and cargo would be secure." 



In these recommendations Mr. Fairbairn has not, he states, 

 aspired to teach the experienced shipbuilder the details of his busi- 

 ness ; all he contends for is greater security for life and property, 

 obtained by adherence to broad principles of construction, of well- 

 ascertained truth. In furtherance of these objects, he also suggests 

 the following improvements and additions to the midship section of 

 iron vessels, viz., the introduction of two cellular rectangular 

 stringers, one on each side of the hatchways, and two triangular 

 stringers, one on each side of the vessel, which run the whole length 

 of the ship, and rest on the watertight bulkheads which divide the 

 ship into eight separate compartments. These cells to be chain 

 riveted, and by the same means to be attached to the angle iron of 

 the bulkheads on which they are supported. ''These will diminish," 

 says Mr. Fairbairn, "the span of the cells and lighten the deck 

 beams, which will not exceed fifteen feet in length from the cells to 

 the side of the ship. It will not be necessary to go further into 

 detail, as the cross beams and gusset stays to the lower deck are of 



