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2nd day 3rd day analysis appearance Area of damper ashes left Average weight Barometer carbonic acid cent centage of combustible cinder left clinker in cinder coal contained coals per hour Cohesive power coke combustible matter cubic foot damper open dried at 212 Duration of experiment Economic weight evaporated from 212 Extremes of external feet Fire lighted foot of coal foot of grate fuel gave gravity of coal Hartley heat inches Initial temperature internal thermometer iron marked matter in ashes matter in cinder matter in soot Mean platinum salt power of coal present quantity seam smoke space occupied Specific gravity square foot steam sulphate of baryta Table temperature of water thickness Vein water evaporated water in boiler water in tanks Weight of ashes Weight of cinder Weight of coals weight of cubic Weight of water Weight of wood yards
Страница 5 - CAPTAIN HAMILTON, RN, to the EARL of LINCOLN. MY LORD, Admiralty, June 28, 1845. I AM commanded by my Lords Commissioners of the Admiralty to send you herewith a copy of a letter from Mr. Hume, MP, with an American Report on the comparative usefulness of English and American coal, &c., and to suggest that you should call on Sir Henry De la...
Страница 17 - Ibs. of water from 212°, this being the reduction of the result given, viz., that 234,210 cubic feet of water at 102° were evaporated by 700 tons of coal. Statements have indeed been made that 14 Ibs. of water have been evaporated by 1 Ib. of coal burned in Cornish boilers ; but as this is the utmost quantity theoretically possible, it is difficult to conceive that it has been realized in practice, even in the best-constructed steam-engines.
Страница 19 - It should combine a considerable density with such mechanical structure that it may be easily stowed away in small space ; a condition which, in coals of equal evaporative values, often involves a difference of more than 20 per cent. 6. It should be free from any considerable quantity of sulphur, and should not progressively decay, both of which circumstances render it liable to spontaneous combustion.
Страница 6 - SiR, — The House of Representatives having, by resolution, required the Secretary of the Treasury to report to Congress, at the next session, such measures as may be necessary for the more effectual execution of the laws for the collection of the duties on goods, wares, and merchandise, I have to request that you will inform me whether, in the discharge of your official duties, any important defects have been detected in the existing provisions. "As it is only by experience that any system of revenue...
Страница 17 - It was found by these experiments, that ll'42lbs. of water were evaporated by every pound of Welsh coal corresponding in composition to that of Mynydd Newydd ; or, in other words, that improved Cornish boilers on a large scale may be assumed to have a superiority of nearly 20 per cent, over that used in these experiments. As the results stated in this Report are only relative, the comparison is not affected by this difference.
Страница 16 - SO,), which each 100 Ibs. of the respective coals may be made to produce. When it is remembered, that the price of sulphate of ammonia is about 13/. per ton, or that 100 tons in coking is capable of producing, on an average, about 6 tons of this salt, its neglect is highly reprehensible.
Страница 19 - Their qualities, so far as regards steam-ships of war, may be stated as follows : — 1. The fuel should burn so that steam may be raised in a short period, if this be desired ; in other words, it should be able to produce a quick action. 2. It should possess high evaporative power, that is, be capable of converting much water into steam, with a small consumption of coal.
Страница 12 - The latter contains one - fifth of its own weight of hygroscopic water ; and the heat necessary for the evaporation of this quantity might be shown by a simple calculation to be nearly equal to 22 per cent, of the total heat obtained by the combustion of the wood The hygroscopic water in coal is however very small, as will be seen by the following determinations of some of the Webb specimens experimented upon : Hygroscopic water.
Страница 5 - Lordships that a similar inquiry should be instituted into the comparative usefulness of the several kinds of English, Scotch, and Irish coals, with the view of ascertaining the best for the naval steamers of this country. I may be allowed to point out to your Lordships that there is a public establishment in...