Hevelius’s depiction of Mons Maenalus, and a confusion of identity


Boötes stands on Mons Maenalus on this plate, Fig. F, from the Firmamentum Sobiescianum star atlas of Johannes Hevelius published in 1690. However, even its inventor seemed uncertain as to what the new constellation should actually be called.

For a start, in some copies of the atlas there is a version of the Boötes chart in which the name of the mountain is spelt Menalis (see illustration below). Evidently there must have been an initial printing of the charts with this spelling, probably in 1687 when the frontispiece of the atlas is dated. This was then caught and changed for subsequent printings, accounting for the odd-looking ‘Æ’ and ‘U’ in the engraving above, clearly modified from the original ‘Menalis’. Most extant copies of the atlas contain the amended version of the Boötes plate.

Yet another variation is found on Hevelius’s charts for Canes Venatici and Virgo, where the name is written with a so-called caudate e, an e with a tail (ę), which was an archaic way of representing the ligature æ.

On the northern hemisphere chart, dated 1686, the year before the rest of the atlas, the name is given as Mænalus, so it is difficult to understand why it was written differently on the individual charts.

Adding to the confusion, Hevelius spelt the name of the constellation in at least four different ways in the text and tables of Prodromus Astronomiae, the book that accompanied the charts. The name is given as both Montem Mœnalum and Monte Mœnali on page 117 of the Prodromus, but as Mons Mœnalus in the index; in his star catalogue he calls it M. Mænalo, while in the introduction to the charts it is listed as Mons Mœnalus, the same as in the index to the Prodromus.