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ds of the 
ers for linear displacements 
THEORY OF THE SEISMOGRAPH. 










A glance at equations (88), (90), and (91) shows that in the record the magnification 
and change of phase of the various harmonic movements of the disturbance are different 
for different periods, and therefore the curve of the record will not be the same as the 





Fic. 47. — Magnifying power of linear displacements. 





and it is not possible by increasing « to equalize the magnification of the movements for 
curve of the disturbance, if the latter consists of movements of more than one period; 
different periods and the phase differences, and make the two curves alike; but it 
might be possible to pick out the different harmonic movements in the record and then 



Fig. 48.— Differences of phase for linear displacements, 




























vel 
to calculate the harmonic movements of the disturbance; we could not, however, deter- 
mine whether these movements were linear displacements or tilts. To make clear the 
influence of damping, I have, following Professor Wiechert, drawn the diagrams, figures 
47 and 48. Figure 47 shows the relative magnifying pow 
for various values of the damping ratio and for different ratios of the perio 
