Miscellanies. 207 



time her bottom was examined and found free from oxidation, the 

 outer scales and rust had disappeared, leaving the bottom perfectly 

 smooth and clean. Now a wood vessel during that time would have 

 required her copper to have been four times renewed, as often recalk- 

 ed, paid and painted, besides frequent and small repairs in replacing 

 defective wood, and at the expiration of that time either condemned 

 or thoroughly repaired, and if we add the value of the time required 

 to effect such repairs, the economy of using iron steamers will be 

 found enormous. 



5. Perfect safety from fire is another of the great advantages to be 

 realized by adopting iron steamers. The returns of steam vessels lost 

 in one way or another, demonstrate that a great proportion of these 

 losses have arisen from fire. It naturally follows that the premium 

 of insurance would be much less for iron vessels than wood. The 

 present custom is the use of wood beams and deck, but were it neces- 

 sary for still further security, iron might be substituted with equal 

 ease for both. 



6. The danger of the vessel's sinking by springing a leak, if not en- 

 tirely obviated, is very much lessened. The facility of dividing an 

 iron vessel's hold into departments by iron bulk-heads, which can be 

 made as tight and as strong as a boiler, is very obvious ; therefore if 

 a leak takes place in any one division, that division may be filled as 

 high as the outer surface of the water, and the vessel be still compara- 

 tively secure. Moreover, a leak at sea on board an iron vessel, may 

 be much more easily discovered than it could possibly be on board 

 wood vessels, as it would not be hidden by a mass of timber. Another 

 advantage would be perfect freedom from the smell of the engine 

 room, which could not reach the cabins, and an entire absence of 

 bilge water, so offensive on board all wood vessels. The plan of di- 

 viding the hold of wood vessels by means of partitions, will doubt- 

 less answer some good purpose, but where so intense a heat exists as 

 in the interior of a steamer, the wood must and will draw; this, add- 

 ed to the working of a wood vessel, would render it absolutely im- 

 possible to make the bulk-heads tight. 



7. The danger from lightning is very much diminished, as the 

 whole body of the vessel is a conductor of electricity. Lander's voy- 

 age to Africa in an iron steamer corroborates this fact, and I find the 

 opinions of the most scientific men concur on this subject. The cap- 

 tain of a steam vessel, who commanded a steamer on the Mississippi 

 more than twenty years, told me that he never knew a steamer to be 

 struck with lightning when her engine was at work. 



8. In tropical climates there is a great advantage in iron steamers, 

 as the internal temperature of the hold would be very much cooled 



