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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. 1922 Excerpt:... where y is measured from the neutral position of the couplings when the s3'lphon and spring are coupled together. Then (15) AqP = (Sc + Ss) y The quantity in parentheses is the stiffness of 'the combination of spring and sylphon and (15a) may be written (15b) P = Sy Experimental Verification of Formula for Equivalent Area. Four sylphons were tested in order that experimental confirmation of the preceding analysis might.be obtained. The construction characteristics of these sylphons are given in the following table: Table 1. No. 1 No. 2 No. 3 No. 4 Internal Diameter cm. 4.1 9.5 4.1 9.5 External Diameter cm. 6.0 11.9 6.13 11.6 Thickness of Material cm. 0.011 0.025 0.025 0.025 Number of Corrugations 11 10 12 21 Material (Brass ) Fig. 2 shows the characteristic curves for these sylphons. The value of Sc can be obtained from these/curves, since from Fig. 3 shows performance curves for Sylphon No. 2 determined experimentally. Extension and loads tending to produce extension of the sylphon are considered positive. The curves are linear over the range shown in Fig. 3. It was found that, when a load producing a deflection of-0.35 cm. was applied, the curve was no longer linear. The points in which the lines L = const, cut the axis of deflections is obtained from the characteristic curve of the sylphon. The points in which these lines cut the axis of pressure may be computed from equation (11) by putting-y3 =0, when or, if preferred, the lines may be drama through the proper points on the axis of deflections with the required slope. This slope is easily proven to be from equation (ll). The slope appears to be negative in Fig. 3, but it should be remembered that the pressures shown here are negative. Fig. 3 shows that Sylphon No. 2 will give linear load-deflection cu...