  A set of HLS was installed in JingXian seismicstation for the tidal
correction of observations from HLS. Harmonic analysis of the data recorded by
HLS and DSQ water tube clinometers in JingXian seismicstation and contrastive
analysis of the results are completed. The tilt tide can be well reflected in
the data of the both instruments and the results are both reliable. The reasons
of the difference between the results are analyzed. The tilt tidal factor is
related with with the type of observation instruments with different damping
constant. Besides, the relations between the frequency response of the
instrument and the tidal factor are discussed in this paper. The current
research establishs a foundation for HLS to be applied in micron-level
precision alignment of particle accelerator in the future.
