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Antonio Colla was a meteorologist and astronomer who made sunspotobservations at the Meteorological Observatory of the Parma University (Italy).He carried out his sunspot records from 1830 to 1843, just after the DaltonMinimum. We have recovered 71 observation days for this observer.Unfortunately, many of these records are qualitative and we could only obtainthe number of sunspot groups and/or single sunspots from 25 observations.However, we highlight the importance of these records because Colla is notincluded in the sunspot group database as an observer and, therefore, neitherhis sunspot observations. According to the number of groups, the sunspotobservations made by Colla are similar as several observers of his time. Forcommon observation day, only Stark significantly recorded more groups thanColla. Moreover, we have calculated the sunspot area and positions from Colla'ssunspot drawings concluding that both areas and positions recorded by thisobserver seem unreal. Therefore, Colla's drawings can be interpreted such assketches including reliable information on the number of groups but theinformation on sunspot areas and positions should not be used for scientificpurposes.

Sunspot Records by Antonio Colla just after the Dalton Minimum