No. 124.] 145 



vessels built of wood. Lastly, the cost of iron, when compared 

 with wood, is decidedly in favor of the former. 



Grantham, on page 41 says: 1st. " A sailing vessel not exceed- 

 ing 300 tons burthen, is equal to a 12 years timber vessel of the same 

 external dimensions. 2d. Iron vessels of 300 tons burthen are rath- 

 er less expensive than wooden vessels. 3d. The larger the vessel 

 the more in favor of iron in the first cost. These estimates are for 

 vessels having like finish." Iron vessels in hot or tropical climates 

 are healthier and cooler than wooden vessels. This fact has tended 

 to increase the number of iron steamers and sailing vessels used in 

 British India. The late unfortunate expedition to Africa, under 

 Capt. Trotter, has demonstrated the superiority of iron over wood in 

 point of health and preservation of life. His opinion on this subject 

 (which has been published) states, that the "mortality in wooden 

 vessels is at least double that in iron vessels." It is stated in Grant- 

 ham's work, page 5S, that " in tropical climates iron vessels collect 

 shells and weeds — and that on entering fresh water it always de- 

 stroys them, as they are bred in salt water, and the weeds that col- 

 lect in fresh water under tropical climates, always drop off as soon as 

 the vessel reaches the sea." And it may here be stated that experi- 

 ence confirms the fact, viz : that iron vessels sailing part in the sea 

 and part in fresh water — for instance, from Liverpool to Glasgow, 

 &c. ; their bottoms are uniformly clean, bright, and rather polished; 

 and further experience proves that the same mechanical principle 

 which prevents iron from rusting or corroding while in iise, alike op- 

 erates to prevent an iron vessel's hull from rusting while in active 

 service ; and it is known that an iron rail of a railroad, will rust 

 away much sooner by lying exposed to the atmosphere, than if in 

 active service by the car-wheels, and almost every person is aware of 

 the simple fact that all kinds of iron machinery, iron tools, &c., will 

 wear more than twice as long in active service, than they would ly- 

 ing exposed to the atmosphere and not in use. This active wear or 

 working agitates the crystals or particles which compose the iron, 

 &c., and the effect is to prevent rust. 



The following facts are selected for the purpose of illustrating the 

 reason why the wooden vessels are more liable to injury or a total loss 

 when on alee shore than iron vessels. Iron vessels, in consequence 

 of the whole structure being so perfect in the combination of the 

 several parts, aiising from the fastenings being of the same texture 

 as the portions of the materials brought in connection with each oth- 

 er, gives such strength and stiffness to the hull, as almost to bid defi- 

 ance to the violence of the sea: while in a wooden vessel it is known 

 that the m.etallic fastenings act not only chemically but also mechani- 

 cally to accelerate her destruction, for as soon as the close connection of 

 the several parts is at all diminished; if blown on a lee shore her de- 

 struction is almost inevitable. The iron steamer Grantham, on the 

 river Shannon, was by accident, run high and dry on a rock. After 

 two days, when she was fairly afloat, it was found that she was per- 



[Senate No. 124. j T 



