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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1910 Excerpt:...well as the most convenient. Fig. 22 Diagram No. 1 Pressures Diagram No. 2 Pressures 65) 75 85 10) 595.5 M.E.P., 59.55 M. E.P., 69.75 Heights Op Divisions Measured On A Strip Op Paper Diagram No. 1 Square inches, 4.43 Length, 3.72 Average height, 1.101 M.E.P., 59.55 lbs. Planimeter Measurements Diagram No. 2 Square inches, 4.46 Length, 3.73 Average height, 1.195 M.E. P., 59.75 lbs. CALCULATING I. H. P. Let a = the area of the head end of the piston in square inches. Let r = the area of the piston-rod in square inches. Let s = the stroke of the engine in feet. Let n = the number of revolutions per minute. The I. H. P., or indicated horsepower, of the head end of the cylinder, is a X (M. E. P. of head end) X s X n 33.000 The I. H. P. of the crank end is (a--r) X (M. E. P. of crank end) X « X n 33,000 The I. H. P. of the cylinder is the sum of these two. If the M. E. P. and the revolutions per minute are each made equal to 1 in the preceding expressions, then the result obtained from each is the I. H. P. per pound M. E. P. at one revolution per minute. These factors are called the engine constants. The engine constants for the two ends are respectively a X s, (a--r) X s and 3:5,000 33,000 If the valves of an engine are well adjusted and the M. E. P. for the two ends of the cylinder is nearly the same, an approximate calculation of the indicated horsepower of the cylinder may be made by multiplying the average M. E. P. of the two ends by the number of revolutions per minute and by the sum of the engine constants. DISCUSSION OF M.E.P. The indicator card from one end of a cylinder shows the pressures on that end during a revolution, or a stroke forward and a stroke back. The Mean Effective Pressure, M. E. P. (improperly named perhaps) used in figuring horsep...