84 KEPOUT — 1861. 



of the system of calculation for any service, lias been adopted as the unit of 

 performance, namelj', the performance of a ship of 5000 tons displacement, 

 employed on a passage of 3000 nautical miles and steaming at ten knots per 



hour, — the coetficient of performance, by the formula j--j—j^ = C, being 



C=250, and the consumption of coal being at the rate of 21bs. per indicated 

 horse-power per hour, which data have been assumed as the base of the fol- 

 lowing tabular statement, consisting of 21 columns, the purport of which is 

 as follows : — 



Column 1st. — Reference to divisions or sections of the subject under con- 

 sideration. 



2nd and 21st. — Designations of the vessels referred to in the various 

 sections. 



3rd. — Size of the ship as determined by displacement at the draft to which 

 it is intended by the constructor that the ship shall be loaded. 



4th. — Steaming speed at which the vessel is required to perform the 

 passage. 



5th. — Coefficient of dynamic performance of the vessel by the formula 



— —— — ^— =C 



Ind. h.p 



6th. — Consumption of coal per indicated horse-power per hour expressed 

 in lbs. 



7th. — Coefficient of dynamic duty with reference to coal consumed by 



formula — tt^ W being the average consumption of coal expressed in cwts. 



per hour. 



8th Power required to propel the vessel at the required speed expressed 



in indicated horse-power and calculated by the formula, indicated horse- 



V^D4 

 power =^ — p-^ 



9th. — Length of passage to be performed by the ship without re-coaling 

 expressed in nautical miles. 



10th.— Weight of hull, including all equipment complete for sea (exclu- 

 sive of engines, coal, and cargo), taken at 40 per cent, of the load displace- 

 ment. 



nth. — Weight of engines and boilers in working order, including all 

 equipment for sea, taken at the rate of 5 cwt. per indicated horse-power. 



12th. — Weight of coal required for the passage, calculated on the fore- 

 going data. 



13th. — Cargo, as determined by the load displacement less the weight of 

 hull, engines, and coal. 



14th. — Investment in the hull of the ship, including rigging, furnishing, 

 and all other equipment complete for sea, taken at £50 per ton weight of hull. 



15th Investment in the engines, including spare gear and all equipment 



for sea, taken at £15 per indicated horse-power. 



16th. — Total investment in hull and e4)gines. 



17th. — Comparative rates of freight or ratios of cost expenses per ton of 

 cargo, being proportional to the investment divided by the tons weight of 

 cargo conveyed. 



18th. — Ratios of cost expenses per ton of cargo, with reference to that 

 incurred by ship A, taken as the unit of performance, and which is expressed 

 by the number 100. 



19th. — Ratios of cost expenses per ton of cargo with reference to the cost 



