  The near 155 days solar periodicity, so called Rieger periodicity, was first
detected in solar flares data and later confirmed with other important solar
indices. Unfortunately, a comprehensive analysis on the occurrence of this
periodicity during previous centuries can be further complicated due to the
poor quality of the sunspot number time-series. We try to detect the Rieger
periodicity during the solar cycles 3 and 4 using information on aurorae
observed at mid and low latitudes. We use two recently discovered aurora
datasets, observed in the last quarter of the 18th century from UK and Spain.
Besides simple histograms of time between consecutive events we analyse monthly
series of number of aurorae observed using different spectral analysis (MTM and
Wavelets). The histograms show the probable presence of Rieger periodicity
during cycles 3 and 4. However different spectral analysis applied has only
confirmed undoubtedly this hypothesis for solar cycle 3.
