Forged Steel Water-Tube Marine Boilers (Paperback)

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1901 edition. Excerpt: ...a sea of ignorance where the only things that keep afloat our desires for comparison, are cut and dried assumptions that nine times out of ten have no counterpart in fact. What right have we to assume that the Ohio coal, or Western Pennsylvania slack, burned under the boilers of the large ore-carrying vessels of the Great Lakes, is the same or equivalent to the Welsh or the Cumberland coal used by the transatlantic flyers? And yet, that is exactly what we do when we compare the 1.6 pounds of coal per indicated horse-power of the transatlantic service with the 1.8 pounds of the Lake practice, to the disparagement of the latter. As a matter of fact, the best ships of that remarkable fleet of grain and ore carriers on the Lakes equal or even exceed in the matter of efficiency the larger units of the ocean greyhounds. But, it is only in the light of a reliable EXAMPLE: Suppose it is shown by a boiler test that 10.4 pounds 0f water are evaporated from and at 2/2 for each pound of dry coal consumed; and that the coal, tested in a Mahler Calorimeter, is found to contain 13,400 B. T. U per pound. To determine the efficiency, find the intersection of the vertical line 1jmco with the horizontal line 10.4. This falls on the inclined line 75, showing the efficiency of the boiler to be 75 per cent. coal calorimeter that we are able to recognize such facts as these, and to realize that without such data, terms like "coal burned per indicated horse-power," and "water evaporated per pound of coal" mean practically nothing when used as a basis for comparison. The method of determining the heat value of fuel that at once appealed to pioneers in this work, was the burning of a sample of the fuel in a vessel surrounded by water, and, by...